Can you guess what is wrong with my revolver and Sand Burr

[Thor]

Warthog, have you contacted Ruger for options? They might offer the service or the frame might be compatible with another cylinder.

 

[Hookeye]

Not that many parts to a Smith revolver.
I'd pop the sideplate and inspect/clean.
Works SA but not DA, hammer doesn't move...........had one that did that. Trigger wobbled enough to miss sear on hammer.
That was due to the trigger pivot pin being cracked. Only the sideplate hole for pin was trying to maintain trigger alignment.
Smith fixed it, early 90's. Cost me $5