If you're a fan of Dunlop balls then I've tried the Dunlop LoCo Bite and they're another ery good cheap ball. Long and straight yet spinners of the wedges. AGD were sellign them for £9.99 a dozen recently...

Try Argos, they sell topflite Z balata £15 for 24. I use them all the time, good distance and lots of stop when you need it, so the price it doesnt hurt the wallet when the wayward shot takes over

Word of warning on the old Z Balatas. Anybody with a slicing or hooking swing, or struggling with moving the ball a lot in the air is gonna have a hard time keeping these balls on the course. They are high spinning balls that will punish a slice big time. Cheap they may be but at what cost ?