Don't waste money on a SA scope mount. Do some reading here http://www.m14tfl.com/upload/
and here http://sadlak.com/si_improvements_to_bpt.html
Sadlak makes the most popular mount for the M1A and has different styles/materials.
I've had 3-10, 6-20 and fixed 10X scopes on my M1A and I really like the SWFA 10X42HD.