It's $1,095 instead of the $500 mentioned at the start, but Dynon has a very good answer: http://www.dynonavionics.com/docs/PocketPanel.html. It's self contained from a company that has specialized in EFIS technology for years, not someone that lately has tried to add the capability to their devices.. It also has Bluetooth out so it can be connect to a phone or ipad app.

I've been using a Dynon D10A for IFR flying in my HP for the last 4 years. It's a full panel mounted EFIS. I've been very happy with it.

Charlie