need help fixing a Baikal airgun, model ИЖ-38П

[Ravenswood]

a couple weeks ago, I bought an air rifle at the local flea market. however, when I brought it home, I discovered that the trigger was stuck. I managed to un-jam it, I discovered that the gun would not cock (the barrel would lever downwards like it was supposed to, but did not lock the piston in place). Does anyone have photos of the internal mechanism?

thanks!