Dr pepper vendo vf63-7 door question

Hya Everyone,

Just got a Dr. Pepper Vendo VF63-7 for free from a friend that is moving out of state.  It produces plenty of cold air, and except for some surface rust on the back, seems to be in good repair.  

The problem, however, is that I can get the door open!    

(this is where I get technical)  It's missing the little round thingie in the middle of the twisty handle that closes the door.  The twisty thing won't pop out so you can twist it and the hole in the middle of the twisty is too small for my fingers.....

HELP!!!  It's a great little machine and I wanna be able to stock it!

Thanks in advance,
Kendawg