[andrewas]

A key ring would be a fantastic idea. After all, keys are small and numerous.
unfortunately, there is no such item. Luckily, keys are never needed outside their quests. The key to De'arnise becomes useless as soon as Torgal falls. So you can chuck them. But I would still prefer a keyring.

If you are worried about losing a vital key, choose a barrel, chest or table somewhere convinient (waukeens promenade for example) and keep them there.