I just skipped thru 2865 current ebay listings and unearth the following. I endorse none of the sellers so it's buyerbeware. Just a random sampling of what I consider frame building 'potentials'.

http://cgi.ebay.com/Meco-Aviator-Jet...item33636115b4

http://cgi.ebay.com/Harris-H-19-2S-M...item1c17d4bda1

http://cgi.ebay.com/Vintage-Prest-O-...item56416c4d8a

http://cgi.ebay.com/VICTOR-TURBOTORC...item255e78ca3f

http://cgi.ebay.com/PRESTOLITE-99980...item3360c7ea15

http://cgi.ebay.com/NEW-SMITH-ACETYL...item35abcbc522