My left drive arm came free on my ride this morning. Seems like the bolt came loose and stripped some threads on its way out. I can’t tell if it stripped the bolt, the spindle, or both. I’m hoping to salvage this with just a new bolt and/or spindle if necessary. I have a praxis works chainring paired with Oval 520 crank. The LBS thinks that the Oval 520 left drive arms come with the bolt pre-installed and aren’t designed to be removed and replaced. What should I do?