All of your questions can be answered by searching Reed’s website:
The Nov SAT test is the last one for EA https://www.reed.edu/apply/guide-to-applying/instructions.html You could always call/email and ask them if they would take your Dec score, the worst than can happen is they say no.
EA decisions will be mailed Feb 1 https://www.reed.edu/apply/guide-to-applying/first-year/index.html
Have you turned in all of the required documents on this list? https://www.reed.edu/apply/guide-to-applying/international/index.html
Run the Reed NPC https://www.reed.edu/financialaid/first-year-applicants/net-price-calculator.html
Reed, as compared to Skidmore, is more expensive and gives less aid on average to international students (although they do meet 100% of need, but do use loans in their packages. There is no merit aid) https://www.reed.edu/ir/cds/cds1718/cdssech201718.pdf