Thanks for your response

> Packages are partitioned into a main and sub-packages, so that 
> the bloat of un-needed matter is avoided.  UEFI is relatively 
> new, and until Windows 10, not really mandated by Microsoft 
> installations.  Also the needed hardware (a TPM chip) was not 
> universally present, and so that sub-package would seem to be 
> bloat to most people

Understood.

> As to how to get a copy, using an second machine to retrieve 
> the needed package, and placing it on a data stick comes to  
> mind.

But how to get it into the system that can only be booted in rescue mode from my USB stick?
I will try using a second USB stick

Cheers
Bill