Brownell's lists Weaver 2-piece bases 43 for the rear and 42 for the front... #955-010-043 #955-010-042 respectively, at $4.05 each... any number of rings can be tied into them...
Also, I believe the 341 was a product of the '30s rather. than '40s. art
Mark Begich, Joaquin Jackson, and Heller resistance... Three huge reasons to worry about the NRA.