one of the placards from the Subterranean Homesick Blues...
Considering that Lennon's 1969 bed-in "BED PEACE" sign sold for more than $150,000 5 or 6 years ago, something tells me no one here is going to get their hands on a Dylan Subterranean cue card any time soon (if they still exist). Though I don't think Dylan lettered those himself, so they're probably not as valuable as the signs Lennon drew.
The most valuable things that aren't instruments are probably hand written lyrics from any of the 60s or 70s types. Original versions of those things sell for ridiculous amounts of money.
The problem with this question is the "isn't an instruments" caveat. Outside of the instruments, none of this stuff is that interesting. Owning Kurt Cobain's Cuisinart or Muddy Waters crescent wrench - who cares? I can go to the rock and roll hall of fame if I want to gawk at that garage sale crap.
I mean, I know people care. They buy that stuff. I should say
I don't care.
But if you have one of Jimi's wah pedals I'll give you $500 for it. ;)