The PoWAR is thought to have worn green coats with white facings early in the war while at New York, and red coats with blue facings while in the South. Katcher claimed that the late war uniforms were red coats faced blue and/or green
Below is a group of miniatures (click to enlarge) that will be used to represent the PoWAR and some other British infantry serving in the Southern Campaign of the American Revolution. All but one comes from a pack of Continental infantry with round hats (the other is from a pack of Continental infantry with floppy hats). Although intended to be Americans, the hats, sparse gear and coats with cut-down tails are appropriate to many regiments of British regulars and Provincial infantry.

Sources:
René Chartrand (2008). American Loyalist Troops 1775-84. Osprey.
Philip R. N. Katcher (1973). Encyclopedia of British, Provincial, and German Army Units 1775-1783. Stackpole Books.
The On-Line Institute for Advanced Loyalist Studies. A History of the Prince Of Wales' American Regiment. (Retrieved December 11, 2009).