You can get a Street Fire with a built-in rev limiter for $160 nowadays. It has slightly less spark energy than a 6AL but that is really not going to matter for most motors. The Rev-N-Nator alone is $210.

1967 Dodge Coronet Deluxe station wagon

1.03" T-bars, QA1 arms/rods, Cordoba/GM Metric/Volare brake & knuckle, XHDs, Hellwig rear sway, 318 Magnum w/ air gap, 727, 3.23s