Happy Holidays- and congratulations on your VH 12 circa 1922-24. You can check the serial number section of the PGCA Forum, enter your Parker's serial number and determine if factory records exist for your gun.
4 and then 2- the pre-striking weight of the barrels before assembly- the No. 2 frame 12 Parkers, at least in the Trojan through GH(E) series with 28" to 30" barrels will usually run from about 4 to 4-2.. Parker, like Smith, never marked the gauges or the chokes on either the frame or barrels- Your gun may also have WK or K or JG- barrel makers inspection initials stamped on the flats and the proof marks-
The Winchester M21 and the Ithacas (both Flues and NID I am told) had choke markings- the most common were from WS-1 through Full for the M21- on the barrel flats- I believe Ithaca used a numerical system- O for cylinder through 4 for Full.
IMO-the best way to determine chokes is to pattern test the gun with a variety of loads- all barrels in 12 gauge with Full may NOT pattern the same-case in point- I have a PH 12 with 30" F&F barrels- and my Galazan choke gauge reflects that reading- BUT- the right barrel is a bit more open and patterns to a higher POI/POA with the same AA No. 8 1&1/8 oz loads.
I had Jon Hosford of Ann Arbor, Michigan check this gun for me- original 2 & 5/8" chambers- never altered- original chokes- also never altered. I use the pattern sheets at our gun club range, but also mount and shoot at rusty abandoned sheet metal farm machinery parts on the various area farms- the pellets (lead anyway) will leave a grey-ish imprint against the rusted metal- I pick a aim point, mount swing and shoot- so my patterning reflects how I will actually be using the gun- it works well for me, may not for you.
Jent P. Mitchell III lives in VA- Jerry Andrews in West VA- both post here on the PGCA site and also on the LC Smith site- perhaps a contact with either of these gentlemen will lead you to someone who can check over your new (to you) VH 12- Welcome and enjoy- Parkers are indeed fine guns to own and use afield--