Pyxplot fails when printing $ character

[Reed Dier]

Previously functional in Xenial on clean install, now broken on Focal clean install.

Setting a label that includes the dollar sign char $, pyxplot fails with an error about a font.
Any text is fine, only when using the $ does it fail.

set label 1 "\$" at 0,0 hal center
^this is the line in question.
If I change to
set label 1 "anything" at 0,0 hal center
this works fine.

Attaching tmp.plot (referenced below) for reproduction.

Repro steps using multipass on my machine.
First, xenial, working.
$ multipass launch xenial -n pyxplot-x ; multipass shell pyxplot-x
$ sudo apt update ; sudo apt -y dist-upgrade ; sudo apt -y install pyxplot
#I copy the file tmp.plot into home directory.
$ pyxplot -V tmp.plot > test.png ; ls -lh
-rw-rw-r-- 1 ubuntu ubuntu 11K Jan 6 14:46 test.png
-rw-rw-r-- 1 ubuntu ubuntu 237 Jan 6 14:46 tmp.plot

Second, focal, not working.
$ multipass launch focal -n pyxplot-f ; multipass shell pyxplot-f
$ sudo apt update ; sudo apt -y dist-upgrade ; sudo apt -y install pyxplot
#I copy the file tmp.plot into home directory.
$ pyxplot -V tmp.plot > test.png ; ls -lh
file 'tmp.plot':12: Warning: ignoring unhandled DVI special string papersize=614.295pt,794.96999pt
file 'tmp.plot':12: Error: dviGetTfm: Cannot find pfa or pfb file for font tcss1000
-rw-rw-r-- 1 ubuntu ubuntu 0 Jan 6 14:49 test.png
-rw-rw-r-- 1 ubuntu ubuntu 237 Jan 6 14:39 tmp.plot

I have attempted to install further texlive libraries such as texlive-full, cm-super[-x11]; all to no avail.

$ uname -a ; dpkg -l | grep pyxplot
Linux pyxplot-f 5.4.0-59-generic #65-Ubuntu SMP Thu Dec 10 12:01:51 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
ii pyxplot 0.9.2-11 amd64 data plotting program producing publication-quality output
ii pyxplot-doc 0.9.2-11 all documentation for pyxplot data plotting program

$ uname -a ; dpkg -l | grep pyxplot
Linux pyxplot-x 4.4.0-198-generic #230-Ubuntu SMP Sat Nov 28 01:30:29 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
ii pyxplot 0.9.2-6build1 amd64 data plotting program producing publication-quality output
ii pyxplot-doc 0.9.2-6build1 all documentation for pyxplot data plotting program

Hopefully this is enough to help get to the bottom of this.