There are some on thingiverse like this one: https://www.thingiverse.com/thing:4147717
There are also these threads (where I found the one above)
I haven’t tried them yet as I’m still waiting for my SM2 to arrive. I think up to a certain level it might also benefit the laser to carry away any smoke, or maybe even be an alternative for 3D part cooling (in stead of blowing air on it) To be tested obviously 