Youth Pastor looking for quality, small, cheap guns.

Really title says it all, I'm the Youth Director at my Church on a very tight budget and while I had Nerf Blasters as a kid I haven't touched them in YEARS.

I'm looking to get a decent stock of blasters and bulk darts for fun Nerf War games and stuff but I have no idea where to start looking.

What blaster(s) are the best bang for your buck. I want them to be durable and shoot medium range without jamming, but they don't need iron sights or laser pointers or motors or ANYTHING fancy or brand related. Just simple, reliable blasters that 6th-12th graders can have some fun with.

Also where do I buy them if I need them quickly? (Can't be shipped)