On the lower bellhousing bolts I would remove another one and go to a hardware/ auto parts store. I would make sure it is a hardened as well all tho it is going in to AL so any one might do. Make sure the new one you get has as much or more treads then the OEM one if you have to you can get a longer one and cut it or grind it to the right length. If you do that get a nut as well and put the nut all the way on the bolt so when your doing grinding it you remove the nut and it will heal fix the threads. Might need a small file to help clean them up as well.