Yeah I seriously wouldn't bother thinking about it until you hit 80k miles or so. If the belt breaks, it is just an inconvenience. I wouldn't go to the dealership to get it done though. If you aren't on one, find a local car enthusiast forum in your area and see where they recommend going. 700 dollars? Wow. The OEM timing belt part is around 45 dollars from OnlineMazdaParts.com (a very good new vendor on here), and the water pump ..
The first price listed is the price the dealership will tell you it cost, the second is the price on onlinemazdaparts.com (Montgomery Mazda in North Carolina)
water pump, Protege, 2.0L 01-03 $103.95 $83.16
GASKET, Protege, 1.8L, 2.0L 99-03 $7.10 $6.04
timing belt, Protege, 2.0L, Tsubakimoto - 1.6L, 1.8L, 2.0L 01-03 $48.60 $41.31
Grand Total: $130.51
I think shipping is free. When the parts are in just take them to a decent place and see how much they will charge for the labor (probably at least two hours I would think). The timing belt job isn't a "fun" thing to do, and I definitely don't recommend doing it if you aren't comfortable retiming your cams and stuff.