There are several products which meet the requirements.
So an electric instrument can be installed as a Minor Alteration – if I read it correctly.
As far as i can tell, this concession doesn’t help with replacing the KI256 where it is used for attitude reference for an autopilot.
That document was VERY enlightening – THANKS FOR SHARING !
Thank NCYankee for discovering it 
Here’s my choice, hopefully certified by the end of the year when I’m ready to go all electric !
SANDIA SAI 340 QUATTRO
Speed and altitude tapes but isn’t classed as EFIS?
Important since EFIS needs an STC even if fitted on the RHS.
Don’t think it’s EFIS as it just got FAA approval I am waiting for that one too as a back up. Will keep the vac pump though as the ATT/FD and AP are on that one..
quote from beechtalk:
What is key for installation as a backup is whether the backup’s install manual includes data showing how the equipment meets the backup instrument requirements defined for existing glass panel STCs (e.g. Aspen, Garmin). Those STCs define the requirements that apply to the backup display for their system. That means that a new STC shouldn’t be required if the backup’s FAA Approved TSO data shows that it meets the requirements of the glass panel STC.
Peter wrote:
Speed and altitude tapes but isn’t classed as EFIS?
This is for back-up, not primary which will be Aspen.
The SAMs a great product but @ $10K is too pricey
SANDIA SAI 340 QUATTRO
Looks lovely. No if o ky that could replace the six pack in the Cessna 150
