Crosman 105 parts?

Does any body know where I could find parts for an old Crosman model 105 pumper? It was my gandmother's, so it's got some sentimental value, on top of being just an great little starling gun. Not long after I inheritted it, though, the rear sight went missing while on a walk around the back of our property, and I can't find one anywhere. I found a good piston rebuild kit on mac1airguns, but they don't carry any sights for it except a scope rail that is just pointless overkill on a pistol this old and lightweight.
 
I was surfing for Dave Gunter as he ( would have beenn R.I.P. ) the man. Someone in GA ( )?) did take over his inventory but I cant recall the name " the 600 shop " or such maybe.
Dollar for dollar you might try here:

https://www.bakerairguns.com/shop/?category=0&s=105&post_type=product
They all seem a value to me, I might even need one myself.

John