Yeah I went looking for used winches recently. I was amazed how much people thought their old winches were worth. Even so, the prices don't start going up to worthwhile levels until you get to 40 and up. Although I might have paid a premium for one that matched the other side, but it wasn't to be.
The condition of the winch is really important, and if you can't spin them and check for play in the bearings it is a gamble buying of e-bay, hence, it better be a good deal!
1979 Santana 30 Tall Rig