Already addressed medical myself, plus we have an actual ER RN on staff.and OP armor is a trifecta... Weight, price, protection. You can pick any two.
if you're dead set on rifle protection, check out RMA 1003. Level IIIa+ which basically means all pistol and some rifle.
I work in a school and I carry a Vertx EDC backpack with Premier soft armor. it's sized to fit soft armor that's level III. Weighs like 2 pounds and I can't really tell it's there because it has it's own compartment in the back. I have carried the bag around town, flown with it, and it's my over night bag, too. Soft armor that lives in a backpack is easier than a plate, I've tried both. The plate was smaller and shifted around, plus heavier.
I'm not invincible obviously but good enough coverage and I can wear it in the front or back, depending what I'm doing, and some armor in my office beats the PC in the truck.
If you're setting up something like this you should also consider real medical. TQs, gloves, bandages, etc. I've had people hit by cars, fall down stairs, cut themselves, etc on campus but (so far) no actives.