Doesn't look Ainu to me; they had katana-like swords, see example:
http://www.fieldmuseum.org/research_..._jp_ainug.html
This one looks like a modern Chinese production, down to the damascus pattern of the blade and fresh garish paint of the scabbard.
http://cgi.ebay.com/ws/eBayISAPI.dll...MEWA%3AIT&rd=1
Am I off by much?