Nice work, Clint!
That should be a permanent reference piece.
I was at a garage sale last weekend and found two swatches of fabric that were the perfect size for several sets of speaker cloth. They seemed to have about the right weight, with one piece being black and the other tan.
mmmmm.... black & tan, but I digress.
I will test them to see if they are porous enough to allow complete sound.
Otherwise, I have your Clint's Buyers' Guide to Speaker Cloth to fall back on...
dennis
Tanx Dennis.

Later on i'll put some more links.

I forgot to mention e-bay...maybe, because it's so obvious, but here’s an e-bay link :
NOS~VINTAGE~RADIO CABINET GRILL SPEAKER CLOTH FABRIC