Do they motorcycle one piece leathers for a people who are 6ft 5?

You could have leathers made for you personally, it isn't much more than off the rack and sometimes cheaper because you eliminate the 'shop' mark up by going direct to the maker. Don't buy leathers off the rack and pay for them without first trying them on for fit. Good fitting race leathers are snug and shaped for you in a riding position, but standing up and walking you should look like a constipated gorilla. The type of leather used is just as important as the craftsmanship of the maker, refuse split or ground hides, they are cheaper but a lot stiffer. Kangaroo, deer or calf hides are are the softest and best.

You can always buy bigger and have them tailor to fit... Also remember that a suit is not meant to stand up, or walking about... Find comfort in a tucked in riding position... Twist side to side, and have room for full range arm movement... Length is important, as long as they fit under the boots and long gloves you are good...