Cheap 318 performance mods.

Swap meet "Performer" intake- $100-$150

Swap meet 500-625 AFB carb- $100-$150

Local shop dual exhaust- $ depends on shop

Stock Mopar electronic ignition if it doesn't already have it- about $150

Clutch fan if it doesn't have it- $varies but should be about $50

Good quality spark plugs and wires- $varies

Advance spring replacement/tuning- $ought to be real cheap

After that it gets pricey.