You might check on the Northwest Vintage Speedsters website (www.nwvs.org), the Model T Ford Club International website (www.modelt.org), and the Model T Ford Club of America website (www.mtfca.com). I think that you have to register in order to post on each one of these forums but you should be able to find someone who knows the answer to your question. You might also check the Secrets of Speed Society (www.secretsofspeed.com). Hope this helps!
Another great T parts supplier is Don Lang's Old Car Parts in Winchendon, M***. web site is www.modeltford.com