Sideplate screws with buggered heads would also indicate tinkering of the 'Bubba' nature, along with a peeled or lipped edge on the sideplate.
It's not unusual for the front sideplate screw (yoke) to be marked ,as many folks remove this screw when taking out the cylinder/yoke assembly for cleaning.
Also bear in mind; many bores, especially at pawn shops, may look shot out or excessively worn when in fact it's a leaded bore that only needs cleaning....guns don't always get cleaned before going on display.
I had the money till they made me pay
Then I had the sense to be on my way
I had to stay in the underground
I was in the house when the house burned down.