Don't know how large a city you are in. If in a smaller suburban area, you might have to take a road trip up to the city. Large building material suppliers and plumbing suppliers will have better displays.
Here in S. Calif. there are some large design showrooms, such as Standards of Excellence, and Pacific Sales, which are also good places to look at displays.
Check you yellow pages, and possibly just ask a plumber if he knows someplace.