If you are referring to the Vintera Mustang, then no. The SD Custom Shop pickup on the JMJ is unique to that model. It was specifically voiced to replicate the sound of Justin's '66 Mustang, and is not available on any other Fender or Squier model. I believe it is also different from the Mustang pickup that has been available for years directly from Seymour Duncan.
If you look carefully at the size of the pickup on the JMJ you will see that it is physically larger than the pickups on vintage Mustangs, the Vintera, the American Performer, any of the MIJ/CIJ Mustangs, or any other "stock" Fender or Squier Mustang I've seen.
This is a composite photo I made to show the size and location of the American Performer's bridge and J pickup compared to the JMJ, but check out the overlay view of the pickups. The JMJ pickup is longer by about 1/8".
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