Is there any instrument similar to a compass but which I can electrically drive?
Your best bet is to try and use an ADF readout, also known as a Fixed Card ADF (its most likely what you have pictured in your question). There are a few variants of the display out there and it will require some hacking to make it do what you need but it should suffice. As these units are generally considered "older" technology you may be able to get a read out for fairly cheap. On the even older side you can look for a Radio Compass/Radio Direction Finder which is quite similar. 

Note: A heading indicator is NOT what you want. While you could pull one apart and install some kind of drive system to make it do what you want it is not, as it stands what you want.