Not to be an ass, but why did you ask me? I honestly don't know that much when it comes to engine options. If you're under warranty, the cheapest option would be a warranty replacement through mazda. Otherwise, you can always pay for a mazda reman. Other than that, there are quite a few companies that do rebuilds. Do some searching around to see who is recommended, if there's anyone local in your area and who is willing, comfortable and qualified to work with rotary engines. You might want to try asking for recommendations in your regional forum to find out if there are any recommendations in your area.
