The K1000 is very common. Which lens is attached? In general, these sell for between $30 and $60 -- sometimes a bit higher, sometimes a bit lower.

The Robot is a different matter and probably is worth more, depending on condition. Check eBay completed auctions.

Perhaps, at some point, there should be some consideration to a "What's my stuff worth?" category that can be accessed by a temporary logon. This way, you don't clog up the registration database with people who have no intention of future contributions to the forums. They just want to know the value of their gear and that's their primary/only interest. And that's fine.