John,
I should have asked sooner, like a year-and-a-half when I ordered my first composite gasket. I put it aside and barely looked at it. A few weeks ago I sprayed it with copper, still without paying enough attention. I went to put it on the barrels and, no-voila, it's for an A50. (Reeeally asleep at the wheel because they don't look alike). Searched and searched for who sold it to me so I could complain about it if not return it. No joy. Can't figure out where I bought it. Maybe a swap meet. Found a solid one advertised as A7. Nope, showed up as A10. Maybe I'll keep it for the A10. Found the current composite version from a reputable seller. It didn't look very new, having respectable shelf tarnish. I suspect this new build will come apart before too long because I'm rolling the dice on piston clearance (being a bit too big). Obviously the composite won't be reused. Figured I'd have to settle for an A10 gasket, but will definitely follow your advice on one of the suggested sources for bespoke.
Richard L.