I'd go with the 286 duration cam- you're stroke will give you the torque down low and with the increased displacement you're going to need the help up top. The 6200 rpm guideline for that cam will not hold true since you're stroking it. Also, what heads? I'd go Vortec- mostly cause its cheap and easy. Do some porting on the exhaust yourself, and if you know what you're doing, touch up the intake. Polish the combustion chambers and you could run a nice 9.5:1 on the cheap 87 octane- which is what I try to design my engines for. I've seen 10:1 work fairly well on a 383, but with a lager cam and in a more friednly car (Camaro's) In a truck I'd stick with 9.5.
That cam will probably put your peak power at about 5900 rpm- which I think is about perfect for a Saturday night stoplight racer with some gear.