Give me a resistance value and an inductance value and I'll tell you
what the current Miller part number is.

Scott,

This is a pretty special job, a custom stepped coil form with seperate
litz windings on each.
I don't think Miller has what I'm looking for. If it came to replacing
the current choke with another model, I've already got several in the
junkbox. What I'm looking for is an exact match to fit in the old
location. The amplifier I'm working with has a very nice period layout
I'm trying to preserve.

But, what the hay, see below:

The characteristics of the R-175 choke a

Voltage breakdown to metal base 12,500 volts.
D.C. Resistance 6 ohms.
D.C. Current Rating 800 ma.
Inductance 225 microhenries
Distributed Capacity 0.6 micromicrofarad.

Thanks for the help,

Dave Goncalves