new marantz sc7 and sm7 system I bought from Japan in 1979.

I bought this system in Japan when I was stationed in Japan in the Air Force.  The system is brand new with all the originally papers and manuals and boxes.  I also have the ST5 digital tuner that I bought from Japan.  It has been boxed and sealed since 1982 and never been out the box since.  What is the value of the Sc7 and the sm7 now?  I paid 180,000 yen for the sc7 and slightly less for the sm7 in Japan.
Constructed with an untold number of electrolytic capacitors, that are now over 37 years old, it would be a good idea to be certain the pieces are actually functional, before trying to sell them. What you get will depend on the yen a buyer might have for old SS Marantz gear.
To add to what Rodman said, what voltage are they?  If not US, they will need a step/up transformer.
I bought these from Tokyo's Akihabara Electric Town.  These were built for US market and are have adjustable voltages for multiple countries (110v to 240 volts).  They have the US electrical cords.  I have used them with US and European voltages. These are the Gold Anodized versions.  They are awesome when the system is setup.  I bought a set of the big Pioneer speakers from Japan also along with the Top of the line Pioneer PL1000 turntable that has also been boxed since 1982.  I have many other vintage stereo electronics that I purchased from Japan that are also in mint condition.  Dynamic Range expanders, equalizers, Teac tape decks, akia reel-to-reel tape decks, All are with original papers, manuals, and boxes.
You,  "...have used them with US and European voltages." and they're still, "brand new"?   Neat trick!  
So why don't you list them on the marketplace site instead of trying to back hand sell on the forum? And without having this stuff serviced, I say it's all worth the current price of scrap metal...
Thanks for you opinion but I just want to know whats it's worth.  I don't plan to sell any of those items.  I would always keep my possessions no matter what.  I plan on taking them out of the boxes soon and get a cabinet that will hold all of the items because they are very heavy and I have many pieces of stereo equipment.
Some of what you've listed have been sold recently on ebay.  Keeping your eyes on the site will give a pretty good idea of their current worth.  Of course, what people are asking is not necessarily what the pieces are bringing.  ie: (   (