Drum catalogs are of great use to collectors who want to see what type of set they've got, and they are of some use determining age (although I have seen "incorrect" badges pictured in other-era drum catalogs).
There are cases where you could see the price tags and then look at receipts and get really close to when the drums were made (receipts usually have a date on them).
I got my first drum sets at a music store in the 70s and at that time the ordering process was done with the store manager. Even though the catalog pictured various sets these were simply suggestions. The actual drums were all sold piece-by-piece. This allowed for any special requests the buyer had regarding bass drum size, or whatever. Generally collectors frown on setups that aren't "catalog-correct" but I have found that, even though they usually follow the catalogs, they definitely don't always do that, and the set is just as good of a set!
Catalogs were marketing devices used by the drum companies to sell drums--nothing more. Originally the prices were included inside but later they would put a price list next to the catalog so when prices were changed, the catalog would still be of use.
Drum collectors who rely solely on catalogs usually are at a loss to explain why a drum is a different size than pictured on a catalog. Collectors who simply use the catalog to help, and couple that with observations of as many different sets and examples of drums as possible, are more likely to have an accurate idea of drum history.
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