i got a monkey wards canned ham with the power head for $15 in the salvation army in ardmore oklahoma of all places. i was always disappointed with tuslas thrift shops never seen anything there. central oklahoma and small towns in general harbor older stuff in thrift stores. also try estate sales and flea markets. blue collar towns and poorer parts of major metro areas are best for old stuff. also doesnt hurt to befriend vac shop owners. im suprised you havent met kenny in tulsa. hes great at finding machines there as well as his friend chad in kansas city.