As of 2015, two online merchants that offer 1889 Morgan dollar coins online are the Executive Coin Company and International Coins & Currency. Inventory at these websites does change, so the condition of the coins available at any time will vary. These Morgan dollars are priced according to their condition and whether they are circulated or uncirculated.
The Executive Coin Company website clearly lists the Morgan dollar's condition and any defects or special characteristics it might have, such as a nice strike or good detail. International Coins & Currency features images of the coins along with details on condition. Both sites group coins by denomination and type, and they offer a search box to quickly find 1889 silver dollars.