The true collectors would refer to me as an "accumulator". I can't afford the expensive collector pieces. I will replace a missing cleaning rod with a repro. I have replaced "incorrect parts" on some of the rifles I've bought over the years, to bring them back to "as issued" pieces. An example being the Greek 1903 returns from the CMP.
I have a C&R license, and am not into buying and selling (it's against the law to do that with that license anyway). I can count on one hand the rifles I've sold in the past 26 years, and they were duplicates.
The point I was trying to make about adding parts was to maintain the integrity of the piece, and not put something on that was never on it when it left the arsenal. As to Japanese firearms, most parts were hand-fitted at the factory. Adding something that was not original can cause problems. For example, an ill-fitting non-original dust cover can scratch the receiver.
Nice catch on the Type Two.