Book your flight for the end of November. Round trip to Bangkok before the peak will run you $600-$800 from the west coast. Make your way to Tonsai and negotiate yourself a good monthly rate for a bungalow. If you show up before the main tourist season and plan to stay until March, you can usually get them down to around $200/month.
Even with all the Beer Chang and Massuman Gai you can handle, you still won't be able to spend more than five grand all in.
Having travelled both Indonesia and Thailand I am surprised you mentioned Thailand as a good spot for Surfing. I just found a lot more surfers in Bali and on the Gili Islands.
Food was probably comparable in price, but a Bintang being slightly more expensive than an 80Baht Chang :)
Not sure how you got that from what I wrote. As you correctly noticed, Thailand has roughly the same surf potential as Iowa. Possibly Montana. Unless you hit it on just the right day in 2004.
It does, however has some truly amazing rock climbing on the beaches in Krabi Provence. That's why I spend every other winter there.
"I have two obsessions in life: Rock Climbing and Surfing. I'm pretty good at the first, and borderline hopeless at the other, but I'm committed to the point where I've arranged my life so that I can travel for months at a time to pursue one or the other each year."
I think I took from your original post that you do both, hence my confusion. Regardless, congrats on the pursuit, its something I am very envious of!
That's my dream right there.