Go with a CMP M1 Garand, you won't be disappointed. They're all USGI M1 rifles. CMP prices and customer service are first rate. Be prepared to wait a while for one, because they have been slammed since Newtown.
4 manufacturers made M1 Garands: Springfield Armory (the gov't armory, not the current commercial manufacturer), Winchester, International Harvester (IHC), and Harrington and Richardson (HRA). SA and Winchester made them during WWII, and SA, IHC, and HRA made them postwar. All of them are made to USGI specs, but some wartime production rifles don't have as nice a finish due to the demands of wartime expediency. SA made the most M1 rifles, and therefore are the most commonly found M1 rifles. Winchesters and IHC's command a premium price due to their collectibility. HRA are currently the only field grade and service grade rifles available at the CMP due to overwhelming demand. IHC and SA rifles should be available again in a few months.
Many rifles at the CMP are "mixmasters", meaning that they have been overhauled at some point and have parts from various manufacturers. The really valuable rifles that the CMP finds go on their auction site. There are some true beauties on there:
M1 Garand auction link.
If you're serious about buying an M1 then take the steps (really easy: affiliated club membership , ie GOAL, and proof of firearm marksmanship activity) to qualify to buy rifles from the CMP and buy a bigger safe, because you can't buy just one...