I think most years LP offered two colors plus white sometimes. They used the same two colors for the stripes on the sunfish they made. So if you can find out what colors sunfish were offered in any given year, you will know what the Laser colors were that year.
There was no LP until 2008. Before that, PSE in England offered vela-grey boats with red or blue topsides, and also black ones very early in the century. These remained as decreasingly popular options even after the formation of LP, the last ”coloured” boats that I know of being the infamous ”Xmas” Lasers of 2014.
I believe that Vanguard also continued its own colour scheme even after having been incorporated into LP, for as long as they built boats under their own name.