Harry K wrote:
Anyone know of a source? I tried Google and found lots of references
but no sources. Did find one set on Ebay.

Unless you're seeking a particular machine needle to fit a particular
grain sack sewing machine any large sewing needle will work for sewing
heavy fabric by hand.

http://www.amazon.com/s/ref=nb_ss_sg...&Go.x=8&Go.y=9

Also, most marine supply shops will carry sailmaker's sewing supplies;
sailmaker's needles , palms, and thread.

You can also search leather sewing needles and carpet sewing
needles.