Iida (not "Aida") made banjos from junky aluminum shell entry level to excellent professional ones. We'd need pictures or at least a detailed description to give you any idea at all. Post your email query on the "Website Problems, Help..." forum.
I have a 70's iida 240 copy of an archtop rb 800, I think it was their top model. Seemed better built than a gibson from the same era. Nice banjo, I think you can find the old catalog on Paul Hawthorns web site if it's still up.
I think this is the site that was suggested that may help answer your question about Iida Banjo's. Enjoy and if it don't work let me know and I'll try it a diffent way, or you may have to copy and paste to get it to open.