Sir, i mean no disrespect at all. What i say is simply an opinion. We all have elbows, other things, every body's has got one.
The carvings. while the gun is right side up, the carvings are upside down in the photo. The carvings are partly katakana, one of the phonetic alphabet. But this is odd because that alphabet is used to write non
Japanese
words in syllables Japanese people can pronounce. The last character is a kanji. This is suspect because Kanji is used traditionally, they dont tend to mix and match alphabets and wouldnt need katakana to write a word in their own language.
The first X looking symbol is "ME-H", its just a phonetic letter. The second one does not look like a katakana, hirigana or a kanji. The third carved character is a Kanji for "Big" or "large". The fact that is it upside down in relation to the rifle and in two different alphabets makes me cringe a little. Generally the Japanese did not allow them to deface their rifles, carving into the urushi finish defeats the point of having a water proof finish. Also the rifle was a gift from the emperor, the half god head honcho, you wouldnt do that. But then again some one may have. Also the stock had been worked on in the past and some of the finish sanded off, so some one has done some work.
The painted stuff is very odd. yes the later two characters mean "type 2" the two characters above it are suspect. I am not a native Japanese speaker, there might be some rare obscure character long forgotten by modern Japanese, but those are not kanji i have seen. i am leaning towards some one who does not speak Japanese carved some Japanese looking characters (and some real ones) in to the stock to give it a story or increase its value.
but like i said, its just my opinion.