No breach seal, I would assume that this is the "weak link"?
There is no breech seal on the breech face; it is located at the end of the compression tube, instead, like on some old BSA’s.
Ron,I just spent 20 minutes looking for parts for the 513, and it seems you may find some in Europe. The few I found on ebay stated they do not ship to the US (from Russia). I would check back on ebay as something is likely to pop up from time to time.Parts for this air rifle seems scare, compared to the Baikal MP46 M SSP pistol, for example.Along the way, I found some info that might be useful in the future:https://anotherairgunblog.blogspot.com/2009/08/disassembling-izh-baikal-513m-part-1.htmlhttps://anotherairgunblog.blogspot.com/2009/08/disassembling-izh-baikal-513m-part-2.htmlhttp://anotherairgunblog.blogspot.com/2009/08/disassembling-izh-baikal-513m-part-3.htmlhttp://anotherairgunblog.blogspot.com/2009/08/reassembling-izh-baikal-513m-part-2.html