Try these guys
http://www.eautoworks.com/html/light_bulbs.cfm
I know Matrix makes a bulb similar to the Polarg that run about $7 a bulb. There's one other company, but I can't think of the name....
Edit:
Another thing. I didn't think white turn signals were illegal in Ohio. I know the blues & greens are because I got pulled over for it. The cop said amber, yellow & white were ok. Don't quote me on that if you get a ticket.
