Going through withdrawal because i figured out i had a boss frog maxx that wont clear a hardtop so looking though things i found this.

Hard Dog Sport Roll Bar for M1 Mazda Miata

Got a picture from him looks like a M2 sport no diagonals, don't quote me though, no mounting gear, but for 125 seems like a killer deal.

 

It's $10 bucks a piece for each backing plate (you need 4 for a sport) and $30 bucks for all of the washers, nuts/bolts from bethania. Just trying to give some info.