by quadibloc » Sat May 09, 2020 9:25 pm
Off the top of my head, I can't think of a place where this information is collected, although it might be possible to get it from the slot machine serial number database.
In the specific case of the Watling Rol-a-Top, I looked through some Billboard ads; in the June 28, 1947 issue, there is an ad mentioning four denominations being available, 5, 10, 25, and 50 cents.
Go back a few years, to the December 12, 1936 issue of Billboard, and another ad for the Watling Rol-a-Top says it's built for 1, 5, 10, and 25 cent play.
I've found some additional information that may help you. Old issues of Cash Box are available on the Internet Archive. The "C.M.I. Blue Book" listed current prices for used coin-operated machines, and so in 1946, it had information on the existing denominations of a considerable number of slot machines.