need BNC to 1/8" adapter

I need a source or two for BNC male to 1/8" mono plug adapters. I actually
have one of these so know they exist but can't seem to find a place to buy a
few more.

The Bendix King handheld radio has an external antenna jack that is a
standard 1/8" mono jack, but this adapter is needed to connect a standard
VHF extenal antenna.

Thanks
Jim


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