The best solution would be to get a wrecked vehicle and bring the engine and tranny up to more modern standards.
The second best would be to buy a crate motor.
The third best would be to rebuild the old motor.
If you go with option 2 or 3 go with a throttle body or port injected fuel system.
I have a Howell system on my Jeep. These are good people and will build a system to the exact engine/cam setup you have. These systems use all off the shelf GM parts and can be worked on by anyone who knows GM products. Took an old carbureted engine and really livened it up. Drivability is very good! Edlebrock systems are good but very pricey. Holly systems are not recommended.
Howell Engine Developments Inc. - Home
When you build your exhaust you may want to go with a single 3" diameter system for good torque and good flow. I use a Magnaflow muffler which has good flow plus a good sound.