Akito Sendai acoustic guitar

[Bluestrat]

I have owned this guitar since 1982, and I am unable to find out any history of the manufacturer.
The headstock bears the name Akito Sendai in gold letters.
The label inside the body also bears the same name and 'constructor de guitarras' Nagoya Japan since 1936.
It has a model number V-800 and what I think is a serial number 00507.
It is very similar to a Martin guitar, of which I think it may be a copy.
The fretboard is inlaid with abalone and it is also inlaid around the edge binding.
The front is a mellow pine colour and the back and sides seem to be rosewood, but I am not certain.
The neck is mahogany.
Can anybody help with this one?

[Mixolydian]

"constructor de guitarras' Nagoya Japan since 1936"

I'm no expert, but that sounds like Terada Gakki. They often have something like that on their labels.

[Bluestrat]

Thank you Mixolydian, very much appreciated! I shall follow up your suggestion.