You should buy hot glue and motor cloth from Organ Supply Industries
in Erie, Pennsylvania.  I have had no problems with their stuff.  When
I purchase hot glue (and it won't be long now) I purchase a 50- or
100-pound bag from a manufacturer.  When I do I may offer it for sale
at my web site.  I now offer the plastic glue bottles specially made
for fitting into the glue pot without its liner.

D.L. Bullock    St. Louis
http://www.thepianoworld.com/