Hello,
I have posted some extensive info about (Chushin) Bambu and El Maya guitars over here:
http://www.ibanezcollectors.com/forum/miscellaneous/el-maya-top-of-the-line-ibanez-artist-killer-t20346/msg194072/#msg194072
Rokkomann was a brand owner.
Maya (musical instrument CO, Kobe) had it's own factory and contracts with Chushin.
Maya's were economic class guitars, EL Maya's and Bambu's were top quality axes (probably made in Chushin, or parts of it).
And still are.
Hope you find it useful.
Cheers.