I have been hearing a thunk thunk noise from the front end of my 83 vanagon.  it has girling calipers, from all I can tell, it has clips on the pins for the calipers. I am thinking the noise is the pads bouncing around in the calipers.  There is no spring type thing to hold the pads like is pictured in the bently.  What does one call these things? 
 Does anyone know what other more common type of caliper more commonly at salvage yards has the same size one? 
Does any one have 2 laying around they don't need?  
From what I am finding the calipers for these vehicles are only used on vanagons, and busses, and it is rare to find one in the junk yard around here.  

Thanks 
Eric