For brakes, anything that fits a '67-69 Camaro will also work on any 64-72 Chevelle for both front and rear.
If you can find a set of camaro rear brakes off 93-97 (parking brake on caliper) or 98-02 (parking brake = mini-drum - better design) you can probably actually get into those for cheaper than the steeltechs, and they'll be 12" rather than 11".
For front, a good low-priced 13" kit is from KORE 3 which sells a C5 kit that goes on your stock spindle. Bigger = better in most cases when it comes to brakes, regardless of what your car weighs.