This engine is painted (with some license for creativity) in passenger livery and wouldn't have been used (except perhaps VERY late) in freight service. That said, both Lionel and MTH has produced cabooses in various reds for T&P. Any will work fine for your purposes. As a rule, most will be more brightly colored than was really the case, but, since the same is true of the engine, that's OK.
If you are interested, although the T&P did have some very impressive 4-8-2 Mountain-type engines, this particular model represents a New York Central prototype that was painted in T&P Eagle colors for a museum to replace a genuine T&P engine that was disposed of.
But, given the dearth of T&P engines, it is commonly reproduced by electric train manufacturers to enable them to sell T&P for a minimal investment in production costs. I have a Lionel version, myself.