Pace You don't mention whether you're flying on an N-reg, or trying to turn a profit under the combined encumbrance of Cash-and-Aggro plus EASA. If the latter, take a look at this:
http://www.easa.eu.int/ws_prod/c/doc/jaa/TGL-36.pdf
Class 1 EFBs may not pose a problem, procurement-wise, but provision of a "certified power source" and satisfying the requirements in 6.1.1. (a) may well stop you in your tracks - depending on how much your a/c owner wants to throw at the problem. Have fun, also, complying will everyting in Section 7 and with finding the dosh for the inevitably huge charge C&A will levy for their time and effort.
If money is no object, how about Cessna's glass cockpit refit ('twas reported in Direct Approach a couple of months back)? Not yet EASA certified
afaik but you never know - stranger things have happened...