I got mine at Napa (Next day order) $7.somthing
Awhile after I got mine I asked at a local parts house and they had 3 different brands of the MO-3000 in stock.
The metal tip on the MO-3000 is .060 longer and there are warnings about MSD caps and this rotor.
MSD caps are made slightly off center and the rotor tip hits one of the contacts ripping the cap right off the distributor.
They say to remove the distributor and turn it by hand, then grind or file down the offending contact/contacts in the distr cap before running.
With a factory cap you just have to be sure your cap is on straight and lined up.