Check this out: It's a neat custom frame designed to work with standard Tomos moped parts. Much cooler than any of the stock Tomos bikes, too. It's reportedly available through 1977 Mopeds and Warbux Mopeds, among others. And- it's hand made in the US, in Seattle!
UPDATE: The Mototromeo frame is now available for both Tomnos and Puch motors and parts.