Owned by Sidney J Wakefield and operated out of Phoenix, AZ. Wakefield died in 1983.
Most of the early presses have no SJW matrices, but then began to use the same number for both sides of a disc. They also pressed quite a lot of LP’s, especially during the late 60’s and early 70’s.
Matrix info is usually in the dead wax only and usually printed very faintly. It’s easy to miss one. Later on apparently, they used a sign like a tulip (late 60’s - 70’s) but that info is unconfirmed.
Dates, as usual, are approximate. Any additional info or corrections etc can be sent to
Malcolm Chapman and Pascal Perrault.