1950XX would seem to put it into the 1952 date range, but my book says it should have an "LW" after the numbers. Does yours? If not, can you post pictures for us to peruse?
As far as value, the Blue Book of Gun Values puts an 80% model at $225 and a 90% model at $250. I find the book to be 15-30% below aking prices for most guns in my area.
I have three Cobras and paid more than $300 for each, including one I paid over $800 for. But mine are all NIB. I sold a shooter not too long ago that was about 95%, for $350.
Hope this helps.
Peter