Very nice gun and welcome to the forum!
Yep, you have a 32 Hand Ejector but not a "Post War Model". It's a Model of 1953 .32 HE, a later, new model still built on the I frame. However it has the J frame size grip and trigger guard. It appears to have a 4 screw sideplate and was therefore likely built prior to 1956 which is the earliest version of the M 1953s. It doesn't have a model number, only the model name and is therefore known as a 'pre Model 30' because it wasn't officially named and stamped Model 30 until 1957.
The barrel would not have a model name on it even if it was a .32 Regulation Police model. Only the 38 S&W Cartridge guns were so stamped.
The hammer has been bobbed and not 'factory'. Yes you should replace it for both value and ease of shooting single action. Replacements are available from places like PoppertParts, Dave Chicoine and several others, just google.
If you haven't removed a sideplate before and fitted parts, you may want to have it done. Chances are good the hammer is a "drop-in fit" but not every time. Go here if you decide to try yourself and haven't done it before view how here:
http://www.youtube.com/watch?v=KneMUM9rfw4
Hard to tell for sure in the photos but your 32 appears to be in very nice condition and if so worth in the $400 to $500 range.