I imagine HD sells tubing, I got mine from the auto parts store and saw some at Ace Hardware also.
As far as the 60# injectors go I'm not sure if they'll work or not. Your typical HCI 302 can get you about 300rwhp, a little more with a custom cam and the TFS190's so maybe 320-330rwhp. Add on a supercharger, depending on how much boost you run, you're easily in the 450+rwhp range. Lately I've been seeing many stock blocks handle well over 500rwhp and live. Check out "project stock bottom end" on FB, his car is impressive and he's putting about 800hp to the ground. With all that said you'll need to ballpark how much HP you'll be making to know what will be a properly sized injector. From the charts, for a boosted engine, 60# injectors will be good up to 626hp at the flywheel, about 500-530rwhp at 85% duty cycle. So the question is, how much PSI do you plan to run? What is your HP goal? You may need a larger injector however, at 500rwhp, you're near the limits of the stock fuel rail and fuel lines (especially fuel return line).