ProVista won't take very well with other grasses present. It's meant to be a mono stand. Plus you'll completely waste your glyphosate tolerance capabilities with other grass types in there. I just reached out to Scott's directly this morning to inquire about more seed as I just did a spring reno with it and definitely need a bit more to fill in some bare areas. I'll let you know if anyone from Scott's gets back to me on availability. I originally purchased from Yard Mastery

 

@LawnPilot reach out to Advanced Turf Solutions. It's a bit of a process to get set up with them and have them set you up with a rep but they have stock of PV seed. $25/lb though so be ready to pony up lol

FWIW - I have approx. 8k sq ft of ProVista KBG from seed and so far I'm loving it. No more fighting stubborn, obnoxious weeds like annua, triv, orchard grass, goose grass etc thanks to the glyphosate tolerance. Hammer it with N and H2O it like crazy during establishment and it'll take off. There's some good lawn journals on here for PV-KBG.