Those Soviet Hungarians gave me the idea for the colour scheme. Whichever scheme is used, it ideally should have a Soviet Brown border to enable common use of SW. In addition having common borders for various Partisans gives a little room for confusion "Are those our armed civilians or are they theirs?" .You can easily use the BVR counters that come with Festung Budapest, they have the coloring you suggest and are fairly low quality.
I agree though, absent official alternate Partisans, those 347s or GMD 337s, can stand in with just a few SSR tweaks.