David Hall: The 1929-D has a relatively low mintage and, along with the 1929-S and 1933-S, it the last Waliking Liberty half dollar (with the exception of the very low mintage 1938-D) that sells for more than it's silver value in the lowest grades. It is somewhat scarce in the higher circulated grades and definitely scarce in mint state. The 1929-D is not quite as rare in mint state and Gem mint state condition as the 1929-S and it is about the same rarity as the 1933-S, perhaps marginally rarer. All three coins are much rarer in mint state and Gem mint state than the dates that follow.
The typical 1929-D can be very frosty or toned in varying degrees. Strike is usually not a problem though sometimes Ms. Liberty's hand can be a little weak.
According to a notice in the June 1934 issue of The Numismatist (p. 416), collectors could still purchase Uncirculated 1929-D Half Dollars directly from the U.S. Treasury for "the face value of the coins and an amount sufficient to cover the mail charrges by first-class mail."