Bilstein HD shocks....can't beat German engineering so obviously a little pricier than most other brands. plan to get a set for my 72 Burb C20 some time over the winter. not sure if Summit carries the correct part numbers for our trucks yet (particularly the trailing arm rear suspension) but here is a link to a seller:
http://www.eshocks.com/bil_Ind.asp?VC=4Q81&SubChar=Q
my truck didn't have a sway bar either. i fixed that with one from CPP (and matching rear unit not yet installed) but the 1-/4 front bar off an 80's 1 ton or camper special is an awesome upgrade. just be sure to get the drop down brackets for the frame rails, bushings, and clamps from the a-arms.