TDPRI member OaklandA gave me a heads up on another transformer I had previously overlooked. He suggested the Allen Amps TP24. Pretty sure it's another BillM Super Blues Junior upgrade. It is not a straight drop-in for the MMB, the rectifier circuit must be changed. If you can make it work (I can!) there's enough juice for 6L6s.
Pros and cons:
The Weber 22772 is $42. It has five more wires than you need so you need to deal with the extra wires. It will run 6V6s. Don't try to make it run 6L6s.
The Allen TP24 is $75. It still has a couple more wires than you need. Rectifier circuit needs to be modded.
I'm workin' on it... I have a cool "drop-in" rectifier from Fender's parts bin.
I thought OaklandA was talkin' about the Allen TP25 ($89). Tempting! But...
The TP25 is 310 volts on either side of the center tap. We'll use the quicky no load calculator for raw voltage. 310v x 1.44 = 446v with the MMB's SS diodes. That's way high for 6V6s and awfully close to the limits of 450v caps in the power supply. The stock caps are 300v.
I'm tryin' to point out easy low buck solutions.
In theory an MMB chassis is on its way to me. I'll post in Shock Brothers after it gets here.