I own a pair of Beyer Dynamic CK703 SDC mics. Anybody know their value or anything about them?

Hi all,

I just bought a Beyer MC713 over eBay (that is, a CV710n body and a cardioid CK703 capsule).

I know nothing about this mic and have no experience with it, so if anyone else does, yell out! Also, I have no idea on the price either, can't seem to find much info on the mic.

Thanks all,
Jon