LionelPrewarTrains.com

This is a suitcase from a prewar Lionel 550 Miniature Railroad Figures set.   

 

As shown in the second picture, the red cap (not included), who has a left hand that is functionally like a hook, carries the suitcase which is a separate piece.  Because it can be separated from the porter and it is quite small (1" long) it is often lost.  

 

The 550 Figure Set was sold by Lionel from 1932 to 1936.   The figures (and suitcase) are cast metal and were made by the J. Hill company of England.   The 556 red cap was also offered for separate sale in 1932.   There must have been a box for the separate sale figures, but I have never seen one.