Mine is a Vinyl Express R II, Vinyl express rebrands RedSail devices such as those found here
http://redsailcnc.com/products.html#
I bought mine second hand and its a smaller one R450 I believe which it looks like they no longer sell
Checking the specs of the larger ones they do sell they call out HPGL as the language so I assume nothing has changed.
I’m not sure if there is a common one that it would be best to target, looking at Amazon/Ebay the USCutter ones seem popular. Looking at their specs they seem to use HPGL also
https://www.uscutter.com/USCutter-MH-Series-Vinyl-Cutter-w-VinylMaster-Cut-Design-Cut-Software
(Under spec sheets)