I have no idea how to find out all the contracts for any particular piece of equipment, but sometimes info will show up in the Congressional Record - usually when some congress-critter is defending some company within his district or hot on the trail of waste.....

Info from 1964 regarding PRC-47 contracts, including the Bendix bid.

and from 1977

The Marine Corps is replacing 1834 obsolescent AN/PRC-47 radios with AN/PRC-104's

Cheers,