I thought you said you wanted simple?

With a duo, ITE monitors are overkill. A simple floor wedge or "Hot Spot" kind on a mic stand are all you need. In ear monitors are suitable for large, loud stages with lots of instruments. Something you really don't need.

However, as far as IEM go.... the real ones are pretty expensive. If you're doing this on the cheap, try the EP-630 by creative. Under $20 on Amazon and they have great seals and are comfortable. I use them in the studio sometimes in place of my cans. They are my MP3 player regulars.

You can find my music at:
www.herbhartley.com
Add nothing that adds nothing to the music.
You can make excuses or you can make progress but not both.

The magic you are looking for is in the work you are avoiding.