It seems that the go-to is the CB Magnspark distributor,coil,and wires. Either with or without the black box controller.
Jake Raby has been using the 123ignition and really likes the Bluetooth units that you can tune from your phone with a downloadable app.
Most plugs today are 12mm thread if using newer heads, the plug holes are relocated to give more meat to the plug and make room for bigger valves.
You very likely have 14mm plugs.
I have even seen 10mm but as a second plug in a dual plug head.
If you have 12mm, I can recommend NGK DP8EA9. That's what I and a lot of others use.
For 14mm, I defer to others. We really need to know what's in there in order to make a recommendation.