Undercarriage percentage is worn. If it's described as 95%, that means it's almost completely worn out. I'm guessing you mean it's only about 5% worn? If it goes to auction, I would guess it'll get a good price - 12k seems reasonable even for an old clunker but with new-ish undercarriage. Those components are probably 5-6k or more alone
Restored as a member
Location probably has a lot to do with what one is worth along with condition. Just for an arms length comparison, my neighbor bought a D7-3T with a nice dozer blade and what I would consider good usable condition with undercarriage 50% and he paid just under $4000 from east central Nebraska two years ago. It is 1954 pony start. He has been using it to push cedar trees out of a pasture.
I sold a 47A last year equipped only with 2 valve rear hydraulics. Direct start, UC was every bit of 50% with tall grousers. 13,500.00 N. California. I only sold it because I had others similar to play with.