In July 2012, we (the Niagara Military Vehicle Association
www.nmvac.org) had to replace tires on two M37's, one M43 and one 15cwt. All the tires were manufactured by Specialty Tires of America (STA) and were ordered through Wallace Wade. They were installed without trimming the bead, although they had to be well lubricated (the tires not the installers). We used STA NDT tires for the 15cwt and STA Superlug tires for the M37s/M43. The Superlug tires look good but more importantly we get a better ride and better road grip than with the NDT's. You can see a picture of the Superlug tires on Wallace Wade's STA web site
They were shipped to a Niagara Falls New York warehouse and after paying the HST at the border we brought them into Canada without any problems or additional expense. Because they are made in the US and are for antique cars there is no duty, just HST. It is much much cheaper to pick our orders up in the US than to have them delivered into Canada. If anyone is interested in the name of our warehouse manager, feel free to send a PM.