It depends on how much you can get for your current engine. But it is better that you visit the Market and get estimates from around 4-5 shops. As far as brakes are concerned, upgrade is only required if you are going to push your car to much higher speeds, wanna do dragging, racing, extreme acceleration, etc within city or on highways. Otherwise, if you are going to drive it normally like ordinary cultus, then the old ones are also okay I think.
Still it is better that you visit the marked and check prices from multiple shops. If possible, try to get estimates for a complete swap including each and everything, otherwise getting each thing done individually may cost you higher, most probably!