They're already on my FTP server:
ftp://ftp.ultimate.com/FastPath/fp4prom/51f1.gz
ftp://ftp.ultimate.com/FastPath/fp4prom/512d1.gz
The first is the first "final" candidate for the 5.1 release (I can't
tell you off hand, that's what shipped) the second is the first
development build for 5.1.2 (which was probably never released - I
think it fixed a bug that would allow SNM (Shiva NetManager) to safely
let fly multiple download packets). I'd go with 512d1.gz
They're probably both binary files sucked out of boxes I had, using
the copyprom.c program located in the same directory, so you'll need
to split them into odd and even, format the data suitably for your
PROM blaster. I think jumpers will need to be adjusted to deal with
the larger PROMs needed... I can look at the settings on mine to tell
you, I can also see which socket is ODD and which is EVEN.