72 DemonWhat year and model do you have? There are only a very few options for most of them......this is assuming that they are stock and not some sort of conversion.
Most of the early drums were not stamped, and have .060 as the maximum you can take off. Most aftermarket drums are stamped, and have .090 as the limit.The drum size will either be cast/stamped into the outer edge of the drums along with the maximum oversize depending on the brand and age of the drums.
Not always a good idea to just buy what came off. The wrong parts could have been installed the last time.
Always refer to the Factory Service Manual.
After staking new drums onto the front hubs, it's a good idea to check the run-out, and turn them on a lathe if needed. Most of the time they won't need much, just a light cut to true them up, but, sometimes they need a lot more. I've run across brand new drums that were so warped, they couldn't be used.A few other things. If buying used drums use a jaundiced eye. Find someone or figure a way to "mike" them to be sure they are not worn oversize, and if used they will NEED to be turned. Drums wear different ways, "belled", "keg" and just plain irregular, as well as being beyond spec
The larger the drums are worn, the worst the shoes fit, because now the shoe dia and the drum dia are much different, and pretty soon the shoes only contact the drum "in the center" area of the shoe. This puts more stress on what little lining is in contact, and glazes/ overheats the lining.