I’ve used this VPBR stuff twice.
1) it’s still available. It’s still ~$74/gal (cough), just ask all the CYA questions if your location says they have to special order it, or it may be even more. Tonight I saw an eBay ad for it at $105.
2) If you want it, find a “substantial” Cummins location...I don’t know, maybe Grand Priaire, TX (suburb of Dallas) is a regional location???. I’ve had mixed results with calling the national number, but face-to-face with local people in Grand Prairie has been great. I walked in unannounced, and within a few minutes I was walking out with 3 gal. (The 3 gals are intended for summer of 2021 and summer of 2022, or maybe even more spaced out than that. I need 1.5 gal per fill. Running it that often might be overkill, but my engine has a fuel dilution problem.)
Last year, I tried to get it closer to home: Ft Worth. It was not a pleasant experience, took a couple tries to get it ordered, they botched the 1st attempt, and when it finally arrived, I got stiffed for an additional $20 shipping (for 1 gal).
The time before that, it went smoothly....but in Grand Prairie again...though I did have to set up an account.
3) There are a couple different part #’s: 877377 & 4337621, both right on the jug. I think the receipt had the 877377 #, but they did have a little trouble finding it in their system...but they had it!!
4) I’m not qualified to tell you it will fix YOUR problem, but it appears to be super stout oil, based on a couple of my UOA’s, and it’s claim to fame is it’s cleaning capability. Supposedly it is high in POE, which might be why/how it “cleans.”