[joeq]

bearing edges can be reworked. Also keep in mind that older drums often have rounder bearing edges to start with than modern drums

I would be most concerned about old drums being out of round. Was this someone's kit who used it regularly, or have these drums been sitting in cellar for 30 years? If the drums were stored in a damp area they may well have warped. This will make them nearly impossible to properly tune. the heads may even bubble or wrinkle a bit.

look for signs of water stains. true roundness may be hard to detect by eye, but when you are looking at the bearing edges, see how well a new (round) head fits. Maybe you could use a level and a ruler. check the N-S diameter against the E-W diameter