The problem with most suppliers is they have no idea of how to do it:( . White front in pressed m/c characters with embossed BSau145d ISN'T an issue to make you just have to think about it and cut down an 11x 8 commercial front plate . Same as what I want , a cutdown XJ6 , or new Rover 75 rear blank and it could be made.
One of the problems is that most are after a quick turnround for no effort or don't understand the law . Acrylic plates are dead easy to make you can even run them off on a computerised printer, we used to have to hand cut them using a pastry cutter type thing with a 40 ton press. Same press was used on clapper dies to press out ali plates.
Nowadays everyone can make number plates in their bedroom. Pressed ali plates used to be tremendously popular with the Commercial guys as it cost a fortune to keep replacing broken acrylic.
Likewise " oh, we can't do 13 x7 because it's not a legal size. The regs dictate the MINIMUM space around a plate not the maximum

The biggest problem is the letter Q , hence why I'm now also trying to track down my mates old equipment.