I've been selling dealer parts for 9 years now and I can attest to the low quality of most aftermarket seals. The aftermarket copies the "specs" of the OEM seal and has a manufacturer reproduce it to the same "specs" but its never quite the same.
I've never had to look one up personally but have you checked a mazda dealer or mazdatrix for the seal?
the orange seal on the right looks like the OEM seal on mazdatrix's website.
http://www.mazdatrix.com/b2.htm
http://www.mazdatrix.com/getprice.as...m=10-556A-1668