Thanks for all the feedback - i've got a street cruiser with a k-member from a latter 60's (69?) Kmember. I believe the front disc setup is OEM correct size. My shocks are pieces of caca and i have old leafs in back with drums in back. My brakes have a new booster with disc/drum MC.
So you already have front discs? Do you need to just replace the rotors and calipers? If so, just call NAPA. If you need a new set up, call Dr Diff and do it right.
Bilsteins are the best shock for the money. You could always go with Monroe's if you are on a tight budget but they are crap in the long run.
I agree with 70chall440, Moog suspension kit from PST is the way to go and get offset UCA bushings to help with camber/caster when you get an alignment.
Suspension and brakes are the foundation of everything and very important for safety. Don't skimp, do it once and do it right.