One thing you can try is rethreading the threads on the strut tower. You may have enough to still bite well. Craftsman sells a good rethreading kit for $50 I think.
But if you don't want to spend the money, I would just drill and re-tap to the next size. Just take your time, use a lot of oil, and make sure you clean the hole very well every thread you make.
Ace hardware has bolts that will work. Just gotta know what thread you are going to use on the strut tower first.
Scott