I tend to the view that Remanifestation occurs among our descendants.
Either way, your best option is to work with what you are at this moment. You may not wake up a strapping Nord but you can align with the qualities which are materialised in that image. Perhaps in a way that many who are close to the physical image have forgotten. I'm three inches shy of your desired height and my grandmother was Norwegian; the suicide rates up there are extreme and it's rarely done for noble reasons. Nobody talks themselves out of it by thinking "Well, at least I'm tall and blonde".
Magic is the art of altering our destiny, but that occurs within a framework of forces/gods which we cannot control. There are things we cannot change. Take it from one who, as a younger magician, made his dreams come true, vanquished enemies and transformed himself beyond recognition, yet who discovered that he wasn't quite the Greatest Power in the Universe™ while lying across a floor in the early hours of the morning, pathetically, powerlessly bargaining with heedless Death as It came to claim his cat.
Accepting the cards we are dealt and playing them as well as we can is an essential lesson. Not accepting them makes everything harder as our mind becomes filled with fantasies of "what could have been" but was never going to be.
Work with the body and the life that you have. If you want to become Nordic, develop self-control (including emotional control) and restraint, actively practice virtue and honour, learn how to use money wisely, defend animals and nature, be of use to the world. If there is a principle which governs rebirth, it will bestow upon your soul what it needs next time around. If there isn't, you'll have still been a person of quality.