Mine was broken in the store when I got it at Whanstalls.....I talked to Rossi USA and they gave me some numbers and then I spoke recently with Gary at Whanstalls and he confirmed that Location Snap Shot in Quebec is now the official parts supplier for Canada. I've dealt with them for Ruger parts in the past and they are not the best comunicators unfortunately!  I called them and left a message about 10 days ago about that screw and sent them an email the same day as well but I still have not gotten a reply.  I will call them again tomorrow.......I'm glad that Rossi is getting some parts north of the border but I'm a bit bummed it's Snap Shot.
snapshots@videotron.ca.