The costumes for those three characters would be fairly similar. They would be simple, as you'd expect for Puritans. The colors would be muted - earth tones of brown, tan, white, black. The fabric would be muslin (cotton) or wool, but it would be rough spun. The women would wear aprons and a white collar. They dress practically; they are all laborers, whether in the home or in the field, and they need clothes that won't be ruined by the work. The colors are muted because the Puritans did not believe in dressing boldly; that would not fit with their ideas of showing respect for God. Also, the natural colors are simpler to work with, avoiding the use of dyes. The fabric is what they would have been able to spin or weave themselves.
The link below is to a costume designer's page; it has some good pictures of traditional costumes for this play.
well, i would not likely expect that the puritans wore much in the way of actual cotton. cotton was not native to this continent and would have had ot be imported from england, and it would have been quite expensive. flax (linen) would have been used though, which grew wild in new england, and wool roving would have been spun into yarns, and of course, the combined fabric of both being "linsey-woolsey", a linen wool blended weave. for the clothing such as caps and collars to be white in color, they would have started their lives as tannish colored, due to the lack of any bleaching agents and the natural color of the flax/wool fibers. the "whiteness" would have occurred slowly, evolving ever lighter through the cycle of washings and being in the sun (whether to dry or because they were worn outside a lot). this would have been the "real" pilgrim look. each person had one or two outfits in most cases, so clothing might have acquired a dingy look over time. the "black" part of the clothing would only be black if the wool was of a black sheep. those were not especially common. early puritans would have sported varying shades of grey or brownish cream, more often than not. they had to deal with what was available on the land, and most early puritans/pilgrims had not any wealth, having been sent to the americas as a form of "banishment". it is likely that as soon as a person was able, they might have aspired to get their hands on black and white and cotton (cotton in those times was the fabric of the ELITE, not the peasants!), if only for church, weddings, etcetera.