Prices for parts and labour vary from shop to shop.
Depending on how the belt failed, extra time and parts may be required (cleaning off old belt debris that got tangled in pulleys etc).
Need to know what engine size, with or without A/C as well as the Alternator size/amps. To be able to itemize cost of belts and labour. But again, my area estimate will differ from where you are and not knowing if other items were affected, makes estimating difficult (need to visually see if it is just a belt swap or if cleaning etc is involved).