Keep my tubes??

So, I decided to cash out of my tubed-based system about a year and a half ago. I intended to get back in when I could. At this point, I'm not sure when that's going to happen. In my day dreams, I'm even considering going solid state amplification.

My question is, should I hold on to my tube collection or, cash that in too?

My instincts tell me that these are old stock tubes are a limited resource and the supply dwindles by the day (at some point, there will be no more right??)

Since I've been out of the hobby for awhile, I'm trying to understand the other side; the demand side.

Should I hold or sell?
You've been with out tubes for about a year and a half which says that you can live without them. Before making a final decision ask yourself "What if anything am I missing?" If you can't answer it you do not need tubes. So there is no longer a need to hold on to them.
For resale, try a retailer that you know and ask her/him what they are worth. Have not dealt with Upscale Audio but have read good things about them and they might be a good source of information. Where you to sell them yourself, the question becomes "Are there enough there to compensate for the time and energy involved?"
Beyond that it is just acceptance of what your answers are.
Recently I offered some NOS tubes for sale. I purchased them 8 or 10 years ago for $300.00. They all sold within 15 minutes for $900.00 to a buyer in Japan. Seems that NOS tubes are a very good investment.
Several times, I have sold tubes that I no longer needed because I had sold a component. Some of the tubes were rare (matched quad of Siemens CCA grey plates in original boxes).

I later regretted selling many of the tubes either because I bought another component that used them, or because I realized the rarity of the tubes and the subsequent lost investment.

So, I'd suggest keeping the diamonds and selling the rhinestones.
It's best if you pack them up and send them to me. I'll keep them safe for you :)
Even Dr. Phil would recommend you keep them.
Tvad said it the best. My regret has always been,.....I should have bought more.

Good luck.
If you don't need the cash now and plan on selling, I would hold on to them and sell them later when things improve. Even though NOS tube prices are still at a premium, I don't think that there are still as many people willing to pay the price.
I think right now is a prime time to sell NOS tubes. Everyone seems to be holding onto what they have so supply is low and what is offered goes fast. If you have "very good" section match and non microphonic tubes they are worth top dollar right now.
I had so many problems recently with NOS tube purchases 12AX7, 7308, 6922 and 6Dj8 that I decided to go to a pre with, yes 6H30E tubes. Point being if this becomes a more common practice the value drops. Also the way things are going the dollar's depreciation may out pace the increase in value!!!
I think I'm going to sell my PW, 7308 and 6922's while the gettins good. All that being said it's still hard to do!!!
Sold all of my 6922 tubes because I purchased a preamp that used 6SN7's. Sold that preamp after 2 years and purchased one that uses 6922's. Regretfully, I wish I would have held on to those 6922's now. Seems like the prices of the 6922's has skyrocketed over the past few years.
05-17-09: Cyclonicman
Sold all of my 6922 tubes because I purchased a preamp that used 6SN7's. Sold that preamp after 2 years and purchased one that uses 6922's.
Did you keep the 6SN7 tubes?
Tough decision but I think Tvad hits the ball out of park on this one.
Thanx for the advice. I have a pair of WE 300b (cherry box editions) that I may part with and keep the rest of the lot. Mostly 2a3,45, 6SN7 and rectifiers.

Willing to trade towards a Nikon 14-24.

Yep Keep your tubes. I made the same mistake too.
Tvad, I sold them all a few months after I sold the preamp. I sold a quad of those russian 1578's and a quad of 5692's here on audiogon. I sold a pair of Sylvania VT231's Ebay.
Cyclonicman...i still have the SLP-98 which i am enloying it a lot..questions please.

what do you think of these 1578/6sn7 tubes to SLP-98 for the front and Syl 6sn7gtb to the rear...good combo?
Until now i am still tweaking some tubes but so far favorite combo's are:

#1 ...T/S r/p 6sn7wgta/brownbase and syl gtb to rear.

#2....Syl 6sn7wgta bwn base front/ Syl gtb to rear

i will try 1578 and Syl w black base/short bottle next.
Pescolar, glad you still are enjoying it. I thought that the 1578's were extremely dynamic, but started to give me some listener fatigue after a while. You really have to experiment with the Cary, but that is what makes it so good. It really doesn't need a matched quad and I found that it sounded better with different paired brands. Overall, I thought it sounded best to me when I used the Sylvania VT231's in the rear position and two ElectroHarmonix 6SN7's in the front. If I recall correctly Cary had Sino Chinese 6SN7's in it as the stock tube. Avoid them, they don't allow the SLP98 to shine at it's best.