I agree with Juneau - there's an awkwardness. "was given his choice of" is the same as "was asked to choose from", whereas "gave his choice" is equivalent to "he chose". Ultimately, the result may be the same, but the sentence is changed slightly in meaning, in the same way as in the difference between 'he was offered' and 'he took'.

This is passive voice: Something / someone gave Clay his choice of ... My best guess would be, that in other words, the second sentence means something like "The design consultant made Clay choose among rather expensive furniture..." As passive voice is a mode rather than a tense, such a sentence is also imaginable in present tense: At the office on Connecticut Avenue, they meet a design consultant who has been retained by Max. Clay is given his choice of rather expensive furniture that happens to be in the warehouse and thus deliverable within twenty-four hours.

I think replacing "was given his choice" with "gave his choice" would sound awkward. You can interchange it with "was allowed to choose among the". Clay was allowed to choose among the rather expensive furniture...