First, the dealer should know the bike year from the VIN number, which I think is molded into the steering stem part of the frame on your bike. One of the digits indicates the year. Do a search on here for VIN and you might find the "code". Also, didn't they supply you with something as proof of ownership, like a Certificate or Origin, title, something with the year?
Anyways.... for bars, I run the Pro Taper SE bars. SE stands for seven-eights (7/8") which is the standard bar clamp size. Plus they are aluminum, and the walls are thicker and much stronger than stock steel bars. They come in different bar bends and colors, and are reasonably priced (around $50-60) compared to oversized bars. If you decide to go with oversized (1 1/8") bars, you would need to buy bigger bar mounts as well.