If you want to be sure to get a new stock with collector grade metal, you need to spend the extra and order the Service Grade Special, that's what I did and I ended up with essentially a "brand new" M1.
FWIW, I have heard that the regular Service Grades for the past year or so are amongst the nicest the CMP has seen for many years so you stand a decent chance of getting one you will be happy with but if you want to make SURE that you get something like this, you need to order a Service Grade Special.