Adam,
Let me know if you need any help about the pump. In order of likelihood, it's either a Barton, Champion, or Waterous. If the truck is made by the American Fire Apparatus Co. of Battle Creek, MI, then it's definitely a Barton (their in-house brand). They usually put a builder's plate on the cab floor or doorway, driver's side. Regardless, it's almost definitely of 500 gallon-per-minute capacity. Lot's of fun to play with, easy to use. Means your truck can do something most others can't - it can squirt!
Congratulations on your new adventure!
-Michael