I did this years ago when I installed my MPP coilovers.
When removing the old suspension, the top of the bolt snapped off. It seems that the bolt was cross threaded at the factory.
Anyhow I was able to find the same grade bolt with the proper thread at the local True Value hardware store.
I had to reverse drill the old bolt out. Then I had to retap the threads. Then the new bolt easily installed back in.