Good idea, get your cscs now, especially before they change any of the requirements. You sound like a carbon copy of me when I was in PT school!!
As for the SCS, you will need the 2000 hours of "sport-specific" practice by the time you register for the exam. So it may take you at the least 1 year after PT school working full time in sports rehab before you are eligible to take the board exam. The test is only given once a year (I think in Feb/March) and you have to had registered by the end of July the previous year.
Once you're registered, you have as much as 7 months to study (July to Feb). However, there are no specific books to study like with the PT boards or the GRE. That's why the clinical experience is so important.
The sports residency is the other route in which the requirements have been brought up in previous posts. Some residencies start in the fall while others start in January. They can last anywhere between 12 to 18 months from what I've seen. Some programs also require you to work for them for a year following the residency (eg. Pitt). In the end, you get sports-specific rehab training and are eligible for the boards after finishing. It's a great way to get mentored in the sports field as opposed to learning via continuing ed, reading books, and trial & error. Pay is much less as a resident but you should be able to defer your loans for a year. I know a few people who have gone through sports residencies and each one said it was well worth the experience.
As for the Olympics, I believe you need to be practicing for 5 years before you can go through their "volunteer" route. Check out this website:
http://teamusa.org/content/index/3623
It is not the only way to volunteer (of course if you know the right people or have the right training, there are ways to streamline through this process).
Hope that helps to plan your career timeline!