Yep; that's none other than the renowned Masakazu Eguchi in his "Mr. Famous" getup. Eguchi would traditionally dress as the Mr. Famous character for promotional events and tournaments back in the day. More recently, he's was occasionally spotted wearing the 'ol lab coat during the production of Mega Man Legends 3. I wonder what he's been up to these days?
Anywho, do give me a holler if you happen to come across any other "undocumented" commercials. I'm always on the lookout, but a little help would definitely be appreciated.