Pactra bottles were glass actually (I think I still have a couple of them in storage). The Pactra stuff tended to be the main brand used that we don't see today, although Floquil colors were more likely used on the bigger projects since that stuff would dry so quick thanks to the DioSol thinners (don't light a cigarette around that stuff). Pactra was doing a lot of different military shades long before Testors started their FS Model Master color line in the mid 1980s. I believe it has been documented that at least one of the colors used by ILM on TIE Fighter models was a Pactra shade.
Over in England, Humbrol and Airfix colors I believe were more the norm in the 1960s and 70s and you tended to see them used more on things like the Gerry Anderson models. Not all the colors available back then are around today though. Revell paints from the 1970s I've never really seen, but model markets tended to be a bit more regional back then compared to today. So one part of the country would be more likely to have Pactra paints while another would more likely carry Testors. Given that California was Revell's home state though, it wouldn't surprise me if Revell colors were common there.