The folks at classicautobulbs may have what you are looking for, however, I imagine you know it's not as straight forward as just swapping out incandescent bulbs with LEDs. You likely will also need to install load resisters to each since your resistance flasher may not recognize the low wattage LED. You can upgrade to an LED flasher but that likely opens a whole new can of worms with the rear stop/turn signal lights unless you plan on a complete LED conversion all around. Hope this helps with your research.
Apparently, I cannot post a URL until I have 10 posts, so please add the 3 w's and a dot com to the above source.