Did you check the company's website?
I've been to both the old and new web sites looking for information on older models and it has none. I joined this site and this particular group in hope of encountering someone who would have knowledge of the older models as I need to positively identify what I believe to be a 70's model with an unusual version of the "mirrored A" logo. The lack of responses here makes me think I've chosen the wrong spot unfortunately.
Hi Calvin, when I bought my 5022 I emailed St Louis Music (SLM) because there was a sticker inside that stated the guitar was set-up in July 1986 by SLM. By luck I got in touch with the same guy that set the guitar up. He is still there. There in not much info out there.
Here's a link that has pretty comprehensive information from Yairiluvr. http://yairiluvr.wordpress.com/2009/06/12/sadao-yairi-history-conti...
ooops..needed to back up on the page I copied...here's the link again and be sure to keep scrolling down to read all the information on the site..http://yairiluvr.wordpress.com/
One thing to note from information concerning the Yairi history is that both Sadao and Gaiichi Yairi worked at the Suzuki violin company in the 1920's/1930's and is where they learned the craft of making wood instruments. Violins were the instrument of choice in Japan in those days and guitars were just beginning to be experimented with. Martin's and Gibsons were the model used in their designs, though Spanish guitars were also recognized. I mention this only because Suzuki guitars seem to never have received the recognition they deserve. Guitars made by the Suzuki Violin co. are very well built and fine woods were used in their construction. I have a Three S model from the seventies that I'd never part with. They show up on EBAY occasionally and I wouldn't hesitate to pick one up as they usually go for reasonable prices.