I have my grandmother's recipe for cookies, from the 50s or 60s, it calls for a 5 cent cake of yeast. How many ounces is a 5 cent yeast cake?
As elaborated here, there were two standard sizes of fresh yeast common in the US, small with 3/5 oz, and large with 2 oz.
Without further sources we can not be sure whether the “5 cents” is truly the smaller size as discussed (although it’s reasonably likely).
What I would recommend is that you make your dough with the smaller amount for one very simple reason: Yeast is a living organism, so if you add too little, you simply need to wait a bit longer until it has multiplied enough to give your dough the desired lift. Add too much initially, and you run the risk of an overpowering yeast taste and a dough that goes into overly risen faster than you can shape and bake the cookies.
This also means that you should judge the ripeness of your dough not based on time, but based on visual clues (e.g. “until doubled”), which hopefully should be included in your recipe anyway, because environmental parameters (especially temperature) can and will influence the necessary rise time.