Welcome to the Forum from Pennsylvania.
Getting values sometimes presents a chore, and 'the books' can be way off at times, high or low.
For values, I go to GunBroker auctions and access the Advanced search, then click on 'past sales' and enter my search. When the results come back I ask it to organize the results by 'number of bids high to low'. That way I get to see what the items have supposedly actually sold for and how many bids they had. Other information such as what someone offered for a set price, or a high starting bid with no bids received is pretty much meaningless. So, your biggest challenge may be identifying exactly what you have and doing the correct searches on GB.
Let me know how you make out.