like to help you out, but as i'm sure is true with most collectors, once i found one, i kinda stopped looking for more. C8 is also a tough grade for anything Marx no less "or better". i may be a little too critical, but i wouldn't grade any 6" tin i have over C7+. my general rule for grading something C7 is, "the best condition possible for something that has been played with".
also, if you mean the 20102 red/gray caboose, although it is painted in a similar two-tone scheme, only the NYC boxcars actually provided "Pacemaker Freight Service" as cabooses were non-revenue cars.
good luck...gary