To answer your question...yes, the Blazer brake setup will fit your '84 El Camino.
I think you'd be able to find the parts for less at a U-Pull yard. I bought my setup less rotors for $77.00 with calipers, hubs, and dust shields.
You may want to go for reconditioned calipers, new rotors....and maybe new hubs. So the cheaper you can find them, the better off you are.
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