Beef,
It would be almost impossible, at this stage of the game, to determine exactly how many JW revolvers were actually produced. USFA, throughout their relatively short life, offered several "limited edition" guns. To the best of my knowledge they never succeeded in reaching any of those limit numbers so you can rest assured that, in all probability, they didn't fill those JW limits either.
No doubt in my mind that, had there been a run on any limited edition, USFA would have adhered to their stated limit. Unfortunately USFA's bookkeeping seemed to leave something to be desired. You could never get a definitive answer out of them when inquiring about a specific gun that you might own. As an example; I own a USFA (not USPFA - there were, apparently, examples of both) .38 cal. Richards-Mason, 1851 Navy revolver conversion. An Italian gun with USFA markings. How many were made? I received two answers from USFA. (1) Less than than 50, and (2) probably no more than 36. Bottom line, they could not, or would not, tell me exactly how many were actually sold. Frustrating!
Now that USFA is long gone, so are those manufacturing records. As to how many JW guns were made, your guess is as good as anyone's.
Take Care,
CJF