Some pictures would help us help you but yes it is likely a 47-50 door. It is also possible it could be 51-54 in that the vent window assembly can be removed from the door. Check for modifications to the metal work along the top near where the back of the vent window would go. The vent window doors were pinched down to meet the vent window assembly in that area. Another indicator is the window regulator, 47-50 had a scissors type arrangement and the newer doors had a single arm type regulator.
