[NLRS] Help identifying coax type

[Dave Fugleberg]

I'm trying to identify some mystery coax, so I can hopefully obtain a small
quantity of it or something very similar.

It's a miniature coax, about 2mm outside diameter. Looks tan in color, but
I think that's the colour of the shield showing through a clear outer
sheath.
Solid center conductor.
The braid and the center conductor take solder well without melting easily.
I suspect it's Teflon in there.

There's some of this coax in this DEMI transverter I have that is currently
configured for a single IF. To convert to split IF, I need to add another
BNC connector and a short piece of coax.

I was going to try using some RG174 that I had lying around, but it's more
suited to crimp connections than soldered- the dielectric melts very
quickly, so even trying to tin  the stranded center conductor is an
exercise in futility. I'd much rather use something like what's already in
the transverter, as I was able to easily desolder one end of that and move
it to the right place without damage.

Anyone know what type this might be? There are no markings that I can see.
If you have a foot of it you could part with, that would be great too!
73 de W0ZF