Your are right Orlando, the 1941 requires a Type 1 Flush nut, but the 1944 take a Type III with a square bar I just looked it up). I have been focusing on the trigger assembly mainly and other internal parts. I have no information on sight parts. I also fear the OP rod will also be an issue.
I am intrigued by your offer for Post War NOS parts - can you e-mail me a listing? This may be ideal for a Mini-G.
Thanks and have a good weekend.