I, personally, would go with a networked printer. Mainly because you only have one to maintain. Since your budget covers 5 printers, and to follow with edfair's thoughts, you may want to get two identical network printers. Then, you can also set them up for printer pooling.
Get them identical, and you only have to buy one sort of consumable (cartridge). Having two gives you a backup. If, for some reason, your network were to totally crap, you can always plug one of the printers in directly (USB or whatever) to get your printing done.
If they can't be without their printer for a few days (parts, etc.) then two printers on the network is a great way. The cool thing about pooling printers is that if one is busy, the other will print instead.
If they're just doing black and white printing, might I suggest something along the HP 4200 series....
Just my 2¢
-Cole's Law: Shredded cabbage
--Greg