You can download a Stevenson protractor at the link below. Actually, it combines Baerwald and Lofgren (presumably "B"), too. I've never had any problem printing the protractor at 1:1 onto an inexpensive photo paper. Works fine for me. The only possible caveat is that you have to line it up to the exact pivot point of your tonearm, which I understand is difficult with some arms. Go the the link below and click on the KWillis Universal Accutrak Protractor Version 2.
-Bob
http://www.vinylengine.com/cartridge-alignment-protractors.shtml
-Bob
http://www.vinylengine.com/cartridge-alignment-protractors.shtml