I am seriously wondering about finding its mate transmitter which in this case would be I believe BC 696 .
Right you are, the BC-696 is the 3.0 to 4.0 transmitter. They show up fairly often at Hamfests in various states of dis-repair. I see prices from 25 to 100 bucks depending. Harder to find is the BC-456 modulator, but they are out there. A little patience and you will find a nice one of both.
Connectors and racks are also available but take a little longer to find at fests. The suggestion of the Milsurplus reflector is good advise.