I know there are people who have converted theirs, but looks like it's all been independent work - namely, not available to buy and install (to my knowledge).
Perhaps if you have a 3D printer and you're feeling creative, you could print yourself a mount for cheap? The main risk would be reaching the glass transition temperature of the PLA, causing it to warp. Though it's unlikely with the motor mount. If it's a real concern, switch to PETG.