Food for thought:

The same seller (Tomsclassic) lists the rotors for 99.00.
I found the caddy rear brake calipers for 95.00
Speedway sells weld on metric caliper brackets for around 22.00 a pair. If ya don't mind waiting for all the stuff to come in seperately, a guy could do it cheaper with welding capability. Then ya would have to figure out e brakes if ya want em, otherwise just use regular gm metric calipers which are cheaper.
The advantages of the kit are:

Everything is brand new
It all bolts on, and ya could change back to drums.
It all comes together, and works like it should.
Time!

I bolted on the kit, old parts disassembly and pulling axles included in less than4 hours.
I spent 2 hours of that on the brake cables.