I believe the best source will be Taurus. I had a side plate screw issue a few years ago and what I think I learned is that Taurus makes their own screws and I'd have to wait until they got around to making a new batch and they got a boat ride up to Florida and then mailed to me. In the short term I was able to juggle some sideplate screws from my little pistol into my daughters pistol and get her's up and running. I put mine in the safe and waited for several month and low and behold an envelope eventually arrived with a couple of the tiny screws. I was able to get my pistol back up and running.
I'm not a Taurus hater, I have two excellent revolvers, and a friend who had a couple of good ones. But I do believe that they are somewhat of a crapshoot and you may or may not get a good one. I have decided not to buy anymore. I do remember that the kid I talked to on the CS line to get my screws left me with the impression he really didn't know much about firearms and it took some patients to get thru to him. I was very nice btw, I was after all trying to get something out of him, but they eventually came thru for me.
Always remember that when seconds count the Police are only minutes away!