Responding to Chris' (or, "your") issue regarding leaks, I mentioned steel/rubber composite gaskets, but couldn't remember the name. It was "Cometic". Easy to find on the web. Site doesn't list BSA, but they have made some. Worth an inquiry, I think. Seach the forum for Cometic and there are some posts from people who have bought them. No need for me to explain or hype Cometic, you will come to your own opinion.
Richard L.