First, are those wood or plastic grips? They look a lot like Herrett grips that may have been painted and the wrong screws put in them. If they are painted- strip them and with a little work they will look good.
I know about how...well...unbusinesslike Ruger's customer service department can be.
I tried to get a "V" notch rear sight blade for a single six a while back, and they would not sell it to me without a serial number.
I would have ordered it from Brownells, but they were out of stock. It's a rear sight blade for cryin' out loud!
I've sent two guns back to them and they've repaired them in less than two weeks- and they did send me shipping labels both times, but they are extremely frustrating on sales of spare parts- for no reason whatsoever. It makes no sense!