Going back to the preachers, if somebody could do the voice then I would do a few different types.
1) Royalist priest:
I would base his vestments on those worn by Archbishop Laud
2) Parliamentarian/Puritan Priest:
I know John Pym was an MP and not a priest but the style of clothes he is wearing in the painting look stereotypically Puritan. I would probably give a Puritan priest a large hat a la Witchfinder General.
Some other options to add as well
3)Covenanter Priest
4)Irish Catholic Priest
5) Ranters and Levellers
Warlord games released this little vignette a while ago: