Electronic ignition upgrade
Depends on your preferences and your approach
IN NO ORDER
You can buy "Pertronix" kits that fit right inside the factory points distributor. Simple 2-wire hookup
You can "junkyard" source a factory Mopar distributor and ECU and wiire it up, we can help with that, or you can buy new kits with those components
Many of us have used factory Mopar breakerless distributors and adapted them to a GM HEI module.
Then there is aftermarket, so called "Skip White" "ready to run" which is an entire electronic system in a distributor with an external coil
If you have the room there are replacement distributors which "look like" the GM "all in the cap" HEI distributors, huge cap, coil in the cap. Drop it in, hookup power and go
Mallory/ MSD/ Accel, I don't know what all else "aftermarket."