What kind of Engine?

The 48" dynamic brake fan in front of the four smaller 36" radiator cooling fans means it is a phase II or late model F7.

Earlier F7's had a 36" dynamic fan as modelled by Athearn.
 
Here is a photo of one on Ebay:

http://cgi.ebay.com/HO-LOCOMOTIVE-BOX-CAR-TANK-CAR-CABOOSE_W0QQitemZ290098734767QQihZ019QQcategoryZ19132QQrdZ1QQssPageNameZWD1VQQcmdZViewItem


f438_1.JPG