Part of the problem of there not being any left and difficult reproductions, is that almost all were destroyed in the war and the actual plans were written in an obscure Japanese engineering language that few could read. They had to go to old folks homes and find workers that were still alive to get anybody that could understand them......................
I know someone who found a Zero part in a flea market that someone had brought back as a war souvenir.
He sold it for some good money on eBay, I think he said it went to Australia to someone who was restoring one.