Rock auto has slotted and drilled 11.75 rotors, look up 78 Cordoba.
As for aluminum calipers, nothing that is a direct, bolt in replacement. Several options to put other stuff on, like Andy showed you, but no "stock caliper but in aluminum" type options.
Cordoba rotor won't work for a C-body. C-body rotors are 1.25" thick, B-bodies are 1".
I would look elsewhere for weight savings. The less rotor mass you have the less heat handling capacity you will have which means less repeated brake application capacity.
Kevin
