If memory serves they sold some blued Troopers with interchangeable cylinders in the early 80s but...I'm not sure. It ceratinly wouldn't be as quick or easy as a Colt New Frontier or Ruger Single Six cylinder swap.
I have a 1980 .22 WMR Trooper III and was told a bit after I bought it I could get a .22 LR cylinder but I never confirmed or pursued it.
Check with the guys on the Colt Forum. They are a pretty good bunch and I'm sure someone could confirm it either awy.