Of course, you have the further challenge of requiring a prescription. Its prohibitively expensive, of course, to buy sets of interchangeable prescription lenses. But some makers offer you the chance to buy one prescription lens set, then fit different tinted/clear lenses over the correcting lenses. Smith's popular Moab HP glasses (www.smithoptics.com), for instance, are available with an "ocular docking station" for the prescription component. Price is $125, plus the prescription lenses. Performance, meanwhile, sells its popular Radial II Multi-lens system with a snap-in RX adapter ($65 for glasses and adapter).
Both the Smith and Performance glasses come with three lenses. As a general rule, dark brown or gray lenses are used during on bright days, as they offer the best light blockage. I prefer yellow lenses on rainy/cloudy days or when trail-riding during daylight hours. Yellow lenses brighten things up until it hits dusk or nightfall, at which time they still do block some light so darken things quickly. That's the time for clear lenses, although those also work well on cloudy days.
With prescription inserts and the right lens, youll always see clearly.