Try contacting MicroScale. I've never heard of them doing any Z stuff but then again few people know they did 1:144 scale Navy aircraft decals either and I've purchased several sets in the past. It's worth a shot and maybe they can do them by special order. Should be just a simple matter of them reprogramming the printers sizes. John Barnhill Nor-Cal SP/UP Connection Foothill Rails
Microscale hasn't made aircraft decals in over a decade, when the company was split between SuperScale, which took over the aircraft stuff, and Microscale. Today, they do print aircraft and other non-railroad decals, but they are all contract print jobs for other companies. For example, next time you open a pack of aftermarket airplane or race car decals, take a good look at them to see the name of the company that printed them. They can, and do, custom decal jobs for private individuals or small companies, but they are large press runs of around 250-500 sheets (minimum). Their decals are made by silk-screening, and it isn't quite as easy as one would think for them to make things in different scales.