I seriously doubt you'll find much in an AT tread with a 55 profile, the two just don't go hand in hand - a 55 profile is a short, relatively stiff sidewall, and for off road work you need taller sidewalls that will flex - you might be able to go down on the tread width and increase the profile to compensate, but a 215 is a fairly narrow tire. Personally, I wouldn't consider anything with lower than a 60 profile even for road use, but, that's driven by the conditions of our roads.
Check the door jamb for the tire placard, see if there is an alternate size listed - if you can switch to a 16" rim, you can then stay at a 215 width and go up to a 60 profile which may widen the available choices.
The car you're looking at appears to have been lifted and may be running larger than stock tires, which leads me to my next question - how far are you willing to go to get all terrain tires under there - how much are you willing to spend on
off-road wheels? Suspension lifts, new rims, importing your own tires, possibly "re-gearing".
I've not looked at the new Vitaras, but I've seen enough of them to know that I wouldn't think of taking them too far off pavement.