There is currently some vintage Thompson leaded enamel for sale on Ebay. Here is a link;
http://www.ebay.com/itm/Thompson-Discontinued-Leaded-Enamel-Powder-Opal-Blue-Ultramarine-857-1-08lbs/311316183561?_trksid=p2045573.c100034.m2102&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D28797%26meid%3D8bf8badc8e364838a22d90d096c7565f%26pid%3D100034%26rk%3D4%26rkt%3D8%26sd%3D350648962033
