Yamaha NS-1000M


Hi,
I recently picked up a matched pair of Yamaha NS-1000m 3-way speakers. I was familiar with them because I’ve owned a pair of NS-500s forever and always loved them. The 1000s are in pretty good condition, but not perfect and I’m just trying to figure out what to do with them.
Noodling around on various sites, I find them selling for a wide range of prices from a few hundred dollars up to a few thousand. While, obviously, the condition of those I’ve seen online is impactful to the prices, I’m trying to figure out whether there are other differences or models of 1000s that also create such a wide price range. I’ve seen a couple 1000mm models, but not sure the difference.
Would anyone have any knowledge they could share regarding this model and what makes such a wide range of price values? In the end, I’m trying to figure out what I have and whether I should put money into restoring them or pass them on to someone else for a fair price.
Thanks, in advance, for your input!

lnirkum
Beryllium midrange and tweeter! Pretty advanced for 1976! Regarding the high prices for some on the 'net - that's just plain profiteering! 
A fair price that I would pay for a pair in nice shape would be $800 - 900. About what I paid for my JBL 166's.