I don't believe that any raw score to scaled score tables for recent administration of the SAT are available to the public. However, my conclusion is based on the four tables for the four practice tests prepared by College Board as well as actual data points provided by my two children who took the March SAT. Not as reliable individually but probably accurate in the aggregate, College Confidential has a couple of threads where posters provided raw scores to scaled scores for a number of versions of the SAT that were taken in March as well as school administrations of the test in March and April.
Just to reiterate, only the new Math SAT is consistently more difficult for sure according to my kids who tried two of the practice tests and took the March administration. In reviewing old SAT tables and new SAT tables as well as some data points for the March adminstration, the curves are always more generous on the new SAT than on the old SAT. This is partly what puzzles me - it would seem simple enough to establish slightly harsher curves on the new SAT to avoid the need for a concordance table, at least for the Math section. The new Reading section is actually easier and thus has a harsher curve - missing only a couple to a few knocks your score down to the middle 700's (after converting from the 40 subscale to the 800 scale) whereas on the old SAT you would be around the high 700's to 800.
As you stated, the mapping will vary over time. In fact, the mapping does vary even among the four practice tests as well as among the different versions of the March and April SAT. As you already know, different versions of the old SAT have always corresponded to different curves - missing a single question on the old Math section can result in a score of 770, 780, 790 or 800 although most commonly a 780 or 790. From what I could infer, at least some "school" administrations of the March and April SAT were markedly easier (as reported in the media) than the version my kids took during the "regular" March administration but it would appear that those curves were harsher per data points provided on the College Confidential threads.
