www.odcmp.com used to be the best place for authentic m1's. unfortunetely they are sold out of just about everthing until october.
CMP also requires a variety of additional background information etc. since the rifles are "supposed" to be for personal marksmanship use. Having said that, you can likely find "Service Grade" M1 Garands at many gun shows, with papers from CMP, since they would sell up to 8 per individual at about $200 under market value and didn't much care about the formal "personal use" qualification in practice.
CMP is currently selling high quality M1 carbines, though they just ran through 12,000 Inland Mfg. versions in two weeks of orders, 1 per customer. There will be additional sales of the rarer mfgs after they work through the unexpected backlog of immediate orders for Inlands (including mine) these were on loan to Italy and have just been returned.
In general you can find a wide range of quality in the market. Import marked "Blue Sky" M1s (Garands and Carbines) from Korea came in over a decade or so ago and many were very marginal in quality. There are plenty of CMP Garands floating around ranging from the more marginal rack grade to service or collector grade. A good muzzle gauge would help, but they are not cheap. The bullet test helps (put an M2 ball round point down in the muzzle, and the more showing the better -- 1/4" showing is good, drops down to the case rim is bad) but many gun shows and vendors object to mixing live ammunition and a rifle even in that context. The M2 ball round is also what is used for the Carbine muzzle test since the carbine ball is too short and rounded.
It really just takes some looking, some trust and a little knowledge about what to look for.
BTW, watch out for all matching "rarer" versions. US weapons parts were not serialed to the specific rifle, just mfg marked. During the course of service parts were replaced or swapped frequently with the part mfg being of no consequence. Many people have tried to reassemble "matching" "collector grade" rifles using the parts market to sell the finished rifle at a higher price. Some hucksters have also restamped less rare mfg parts to make them more rare variants (stocks are a biggie). My advice is to just stay away from the all matching unless there is no price differential. Very few US weapons would naturally be all matching after any service use.
The worst btw are now the German rifles and any Nazi memorabilia where "humped" or faked/repo products are concerned. Everything seems to get an SS death head or lightening bolts, even if it never had one or was never marked as such in that specific location. They also have to grind down, restamp and reblue parts to make all matching rifles (since most parts were numbered to the specific rifle), which can be spotted if you basically know what to look for. I don’t know enough myself to currently consider collecting one of the rarer K98k models or an expensive sniper. I might be OK for a more common matching vet bring back at a reasonable market price since the basic efforts of the amature humper are not that hard to spot. One might imagine that 50 percent or more of the rarer types on sale are fakes.
Charon
