well, the one my friend got 'Muffler Thrush Turbo Oval Case 2.5" ID Offset/Center 18.5" Overall Length' is only $18, so...

the inlet was too large for him, and more than likely is for me as well (the 2.25" version is $20), but i didn't know if the length would matter. wish i had a ruler sometimes...
as for the mount, it's not urgent, but i would like to get it replaced soon. it's just the small arm one on the upper-passenger side of the motor that helps stabalize it, but i know that if one mount goes too long without being replaced when it needs to, then the other mounts can wear out pretty quick. those other mounts are expensive, so i'd rather not...