I think you could probably get more for the C3PO as it has nice grades. If you look on vectis and Ebay past sales you would have a recent price to go by.
A 90 grade went for £1,100 and fees, and on ebay there were 2 that are in sold/ completed. 1for £1750 not graded , and 1 graded 85 for £1000. Both stated or best offer so have a look.
If I fancy anything I always try and find an older sold price somewhere for an idea on price.