Looking good Jenkins, I would have a displacement map for the wood to bring the texture out a little. For the keys I would use a mia x shader set to preset copper (change the preset colour to match the ref better) with this you will need to create some reflection maps or reflective lighting then I would bake this so I could take of to photoshop for so grunging.............dave

Edit:forgot to say add a little bump to the copper shader so that bakes out