Sylvania siverstars (Ultras if you can find them) should be a slight improvement over the stock halogens. Just look for them at any auto store.
Whatever you do, steer clear of really blue tinted bulbs. The silverstars have a slight tinting to them, but it's not a HID wannabe bulb. There are also the Sylvania Xtra vision bulbs that have a higher output than standard halogens.
One more suggestion: the GE Nighthawk. I've never used these but I've heard they are good and I think you can find them at Wally World.