In case it's helpful, this is the Japanese K Yairi website. It's not that easy to find with google, I can only find it when I search for my RF-120 model number, which I purchased in Tokyo.
http://www.yairi.co.jp/about/
"Allow" google to translate to English if you want to read the website.
I'm not near my K Yairi for another week or so but when I next have my hands on it I'll take a picture of the manufacturer's stamp if i can find it. The website does say K Yairi is currently made in Kani City, Gifu, which is just north east of Nagoya Japan.