Things a WWIIfantatic should look for:
Only Springfield Armory and Winchester made M1 Garands during WWII. Winchester ceased production at the end of the war but Springfield Armory continued on until 1958 or so. Springfields below approx serial number 3,800,000 are WWII era.
Almost all CMP rifles are mix masters. You might be able to get a WWII receiver but the barrel may be from the 50's or even have parts from International Harvester or Harrington and Richardson who also produced them during the Korean War era. Not really a big deal as almost ALL were rearsenaled at some point. A "newer" 50's barrel is acutally kind of a good thing as they will usually be in much better condition. One other thing to note is the trigger guards, WWII era guards are milled and have a large hole to the rear, later one's are stamped and do not have that.
Just some things to think about and what you can expect (and ask for) from CMP.
Most people are happy to have one, regardless of the parts and dates. I know I am.