Well, Spaw, I'm pretty sure. Nobody played hokey pseudo-Western music like Pee Wee King and his Golden West Cowboys, and that's definitely Hawkshaw on the vocals. I've found several references to a Hawkins/King collaboration on "Slowpoke". Here's one: http://vhost.telalink.net/~nsf/king.html

'Course, you can't always believe everythig you read on the 'net (o,-).