As far as I know you would have to take the bike to the dealer. He MIGHT be able to order another smart key using your unit serial number. However, even if he can do that your bike will be sitting for quite a while.
Currently own:
Red 2013 Honda PCX150 Givi tall windshield & tailbox - Lots of extra lights Custom seat from Thailand - Bad Boy Airhorn Takegawa Lowering Shocks - Michelin City Grip Tires Headlight assy upgraded to LEDs w/HS5 main bulbs NCY variator, drive face, and rollers