I read your post and wanted to let you know that I'm sort of in the same boat! I went to college a few years ago for Fine Art and Biology before dropping out because I realized that I has some self exploration to do: thus the accumulation of debt ensued.
I have similar interests along the lines of Permaculture design (I'm certified as well) and I would like to focus in design/build, yet have had few opportunities to build experience in this area (I live in Pennsylvania).
I suggest that you take a look at the "de-schooling" or the "uncollege" movement, if you haven't already. I'm not a huge fan of the term because it's not truly indicative of it's meaning...either way, it is MORE than possible to develop a career in this area through doing your own studies and getting your own experience. There are infinite, free, educational resources via the Internet. A self-directed learning pathway works like this: You hone in on what you want to learn, create a syllabus for yourself which includes books to read, short courses to take, apprenticeships and internships to do, etc. BUILD A PORTFOLIO of your experience, your successes AND failures. It may take a lot longer than going to University, but with a self-directed education you can choose what you do and your own style of learning. You can be a pioneer in not just the world of Permaculture and Natural Building, but also in the evolution of education. I truly belief that in our field of interest, a degree, with hyper inflation in tuition, could become unnecessary and obsolete (let's help that along so we don't have to be enslaved by debt!!). The sites that I've listed below go more in depth about the process of designing your own education, but what you want to do is really what matters, and overall, EXPERIENCE MATTERS!!
Currently, I'm planning my self-directed education in Permaculture/ecological design, and the next step is natural building, admittedly it takes a lot of self-motivation and I would love to find a peer who is pioneering their own path as a source to bounce ideas off of. If you'd like, I can send you my syllabus thus far, it's consistently changing as I hone in on where I want to go. I too have goals of traveling during my education and my start in that is by applying to the Bullock Brother's Homestead on Orcas Island's skill building program (It's on their site if you want to learn more). I'm saving up a buffer of money to pay for my loans while I travel.
As far as a career in Natural Building, I am not sure how that all works, but I suggest contacting and interviewing natural builders that you know as a start. I think it's possible to develop a career in most anything, but if you are creative and scatter brained like me, a business course (many of which you kind find for free online if you haven't been exposed to it) could be very beneficial.
So, just like Permaculture Design, do a regenerative design of your education using similar principles...I'd be happy to discuss more ideas on this because I have yet to meet anyone on a similar path as me.
..and in closing, BE THE CHANGE YOU WISH TO SEE. Education is a what I feel is necessary for our species to evolve to meet it's amazing potential, and we are tricked into thinking that it has a huge price tag. There are so many free resources, libraries, websites, and just good old DIY to take advantage of and we are beginning to see it!