The Colt Cobra is the Dick Special with an alloy frame. The first ones came out in 1950. In 1973, they got a shrouded ejector rod. AFAIK, they were discontinued in 1981, but Colt later came out with the limited edition Combat Cobra and the King Cobra in .357.
If the gun is the first issue (ejector rod not shrouded), and near 100%, the price would be fair. If the second issue, IMHO, $350 is too much unless the gun is 100% (new) condition.
Jim