(Sorry for the comment on a 2 week old post)
For those in the US, Tire Rack can shave down a new tire to a specific depth for you. You just need to measure the other tire(s) to give them a measurement.
Had to do this for my Subi once and it worked like a charm. No mechanical problems after (although I did sell the car, like, a year later).
"... making you eat..." π