http://www.ebay.com/itm/VTG-1-2-Pipe-FORD-SPECIAL-Bethlehem-Five-Point-Ford-Spar k-Plug-w-Box-NOS/281687552751?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222 007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D29006%26meid%3Dd418a50f66f8408ab2a05fac50e cb4c8%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D121650973482&rt=nc
The Bethlehem plugs looks interesting, but no pipe thread for Model T, must be for later Fords:
The Benton plug is cool (looks a bit like a Splitdorf) but not a pipe thread - and crazy expensive..
And lastly the Schlee plug really looks like it would fit a T - but I think I'll stay with champions. Could be fun with a collection of various aftermartket plugs, but not at those prices for me..