Morven Stroud is a ghostly merchant found within the Soul Cairn. He claims that he used to be one of the greatest merchants in High Rock, but accidentally sold fake ingredients to a person who worked for a coven of necromancers, thus dooming him to the Soul Cairn.
He will trade a sword, battle axe, light armor, heavy armor, or a spell tome for 25 Soul Husks. The item received appears to be random within the type chosen. If asked for a spell tome, Morven will select one at random. Spells of all levels can be given whether the Dragonborn knows them or not. (It is unknown if Master level spells can be acquired). The weapons and armor are similar to random loot generated in dungeons and may be enchanted.
Morven Stroud is found in the northern section of the Soul Cairn, just east of the main path running north-south.
The Elder Scrolls V: Dawnguard (First appearance)