Earlier quoted context omitted.
Except this bit: Please note that in accordance with the license agreement between VMS Software Inc. and HPE, VMS Software Inc. are not able to distribute VAX licenses. Since I've got actual Vaxen it doesn't help.
So back to the original question, what about macro32, the VAX emulator built into VMS on alpha and itanium? Where you have the source, you can build a native binary. Where you lack it, perhaps the emulation is sufficiently robust. https://en.m.wikipedia.org/wiki/VAX_MACRO
I have keys for the VAX assembler (and Fortran, BASIC, and Ada) so running source, and building applications that DECUS distributed back in the day, isn't a problem for me.
What annoyed me was that VMS/VAX support was discontinued by the hobbyiest program. When it was announced and I asked for details they suggested I contact licensing. Which I did and suggested I could buy new licenses for VAX machines for $5,000 good for up to 25 users. For a machine that was headed for the skip. So someone, somewhere, and I'm thinking US GOV here, "can't" upgrade their VAX hardware and HP has them over a barrel so they continue to hold those licenses as saleable products. But that is purely speculation on my part.
[1] In fact, for the earlier models (anything before the VAX 4000 series), they run faster on a modern PC under simh than they do on the original hardware.