...while the older US-made E300 is preferable, I'd only buy it if it is in mint or near-mint condition, like this: http://www.ebay.com/itm/CAD-e300-ori...p2047675.l2557
(the E350 was the gem of those earlier CADs)...a brand new E300S can be had for $30 more: CAD Equitek E300S Multi Pattern Condenser Microphone | eBay
"The E300S is a revised version of CAD’s E300 microphone. The new version is intended to sound the same as the E300(2).
The E300S has the same capsule and circuit design as the older version of the microphone. Like the earlier version, it uses a pair of 9V nickel metal hydride batteries to power the circuit; phantom power, when available, is used to recharge the batteries."
Read more: http://recordinghacks.com/microphones/CAD/E300S