There's a number of ways of doing this, but one that keeps the overall shape/form of your page without adding more pages would be to modify the white area itself as it's own entity separate from the map.
Google+ does this on posts by having a contextual "flip around" icon in the corner, which rotates the post to it's "back" (as if it were paper) to show metrics.
Adding a contact button below the text, you're free to "modify" the text box area in a number of "premium-feeling" ways. Fading into a contact form, flipping 180-degrees, cycling down, or just transitioning in general into the "contact form".
Having a "back" function somewhere once on the "contact" form would "undo" the transition back to the static text.
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