Getting a Simunitions certification isn't that hard. You just have to be a certified instructor, have $2M in insurance, and take an online course. That is it.
The ammunition is expensive along the lines of $1 per round, but unlike airsoft there typically is no argument if you got hit. It hurts like a mother and leaves a paint mark most of the time. Speer has their own generic Simunition FX ammo (the patent expired a couple of years ago), but I am not sure they sell to anyone other than LE agencies.