The reason I say ca. 1890-1910 is that I have seen many tokens of this style and that is the date range they fall in. If you go to
TokenCatalog.com there are photos of many, both attributed and unknown, that you can find that match the style of this one. The mechanism to search for them isn't easy to use, but I would start with the reverse description, using the same format as in the database (i.e. / between lines, ¢ instead of cents if that is how it is on the token) and search for that exact phrase with imaged only entries. You will get a lot of pages of results. While you are there, post yours so other eyes can look at it.
As far as how to find old P.R.Y - I did a quick look at the 1900 Census for Oldham County and saw nobody with those initials. Of course it is entirely possible that somebody brought this token there from Louisville (or another place), figured out he wasn't going back to redeem it, and ditched it in the creek. Another possibility is that P.R.Y. closed his saloon and dumped the tokens he had on hand into the creek. If only this one could talk...
I looked in the 1900 Louisville City Directory classified section and didn't see anybody with those initials in the saloon part. Then I went to the "Y" section of the alpha listing and
may have gotten a clue. There is a Philip R. Young shown as a solicitor (salesman) for the Frank Fehr Brewing Co. He is also shown that way in the 1894 & 1904 CDs. It will take more time to check through all the CDs, but I theorize that in his work as a salesman for the brewery, he may have found out about a saloon that was for sale at a good price, bought it and ran it for a while, perhaps as a side job, and had the tokens made for it.
John in the Great 208