Welcome to the 2WD MS6 club, of which I am a current member, having been a member 2 times in the past as well.
Drive Shaft Shop offers the only available (to my knowledge) upgraded axles. They offer a package on their site for both axles, but you can call and get just the side you need.
I saw that you broke the rear mount, did you replace the front mount as well? The reason I ask is that I broke the driver side axle (OEM), then the OEM replacement, then the front mount (OEM), then the driver's side axle, passenger side axle (OEM), and rear mount (OEM). If you drive your car, this will continue to happen until either the OEM parts bleed you dry or you've replaced everything there is to upgrade in the rear end.
Be sure to find some replacement diff/axle seals, they tend to not work as well after the axle has been replaced.
