The guide I have is a couple of years old, but if indeed it's in close to mint condition, a starting point is $1,250 to $2,500. The closer it is to mint condition--remember, "mint" means "perfect," not "striking," so if there's even the smallest scratch on it it's not mint--the closer you'll get to the upper range. The value could be a bit higher for all I know but I don't have the 2005 Greenberg Guide to check.
But the good news is you actually do have a pretty rare--or at least valuable--train. A lot of trains that people are told are rare are actually anything but.
