Very nice acquisition!! A 1945 Walther! Cool. Is it a dual or single guide lug on yours? Does it have a G43, or a recycled G41 carrier? Couldn't enlarge those pics on that other site...
I've got a duv44 (Berlin-Lübecker Maschinenfabrik) Volkspolizei marked G43. I've got a Durofol handguard on mine, plus I put a nice original early serial # ddx ZF4 and mount on it too.
In regards to repro mags, they may require a little fitting... or a lot.. I got lucky with my repros, they are a tight fit, but they fit! The biggest problem with them is the spring and follower... The springs seem to not be quite correct, and the followers tend to tilt and jam the mag/gun.... Maybe MagPul can make some Anti-Tilt followers for the G43!!??
I've only tried my repro mags once. It was during a Service Rifle Event, and I had the follower tilt and jam, from then on I just used the original mag and topped it up with stripper clips. The mags seem to function fine while function testing with dummy rounds though. I'm thinking maybe I will modify the follower with my own Bubba Anti tilt ideas...
I know ZefArm (hxxp://zefarm.net/) has a repro G43 mag on his site for $125, but I'm not sure if ZefArm is even still in business or not (The site still functions?)... Barring that, try iRunGuns out of Edmonton, Prophet River, or another importer to see if they can get you a pouch or two of them imported...