Hi Wedbike,
Owch, I always cringe when I hear about these injuries as I've heard they can be really painful!
Something like this (not sure if you're US, UK or AU but you can find it on the site here for an idea) http://www.return2fitness.net/Insoles_and_heel_pads/Heel_Pads/P8410sorbothane-heel-pads might help you, however I would speak with your surgeon/physiotherapist first to make sure that it is going to be OK for your particular problem. Sorbs are pretty well known and widely used.
Good luck with the rehab!
Ruth Cheesley BSc(Hons) MSc MCSP
Chartered Physiotherapist