I mean why is that Japanese (or JapWW2 rifles in particular) rifle not worth very much to begin with? Are they not rare?
I've known for a long time about restoring historical pieces being a no-no...Learned that lesson the hard way, probably same as everyone else.
No they are not that rare. Nor are they all that good a rifle, "strong as Hell tho, the early ones". Boy I remember in the '80s they were practically giving very fine ones away.

But they are an interesting piece of history and their value will only go up if left original. No WW2 collection is complete without one or two. There were productions runs made for other countries and/or slightly modified types. Im not really up on Arisaka's but I imagine they would be more valuable.
I used yo hunt out of a small town in the high plains of eastern Montana. I met a guy who'd been on General MacAthur's security detail and after the war delivered mail for the Govt. Every spare cent he had he bought arms from returning GI's and became a huge general collector as well. He had a military collection that would put any museum to shame, including many Arisaka's all with the MUM or Imperial Chrysanthemums. I guess being on his detail had its advantages, that or maybe he got examples from production runs to other countries which left the Chrysanthemums on them.