I'm another one that was originally interested in a Sage stock to use on one of my own rifles until I had the opportunity to play with one whilst installed on an M14 service rifle at work. I didn't care for it as much as I thought I would in the end.
FWIW..... Here are a few things that might be of interest to you.
1. The type we were issued did add 2lbs to the rifle overall, and this is on an average. I have had around 30 different USGI synthetic stock over the yrs, and found that they do not all weigh the same. Variances were up to 1.7 lbs. ( I would have to look at my notes to give more exact figures, but am currently deployed, so do not have access to them at this time.)
I have not had the opportunity to weigh one of the newer Springfield Armory Incorporated (SAI) plastic stocks as of yet, but hear that they outweigh the GI synthetics on average.
2. The Sage stocks that I have had in my mitts all had the cutouts for the selector lever, as these stocks are being used for actual M14's. I do not have a use for them when it comes to my POF M1A/M14S types, as mine are all purpose built semiautomatic only receivers. also learned the hard way that the "gaping hole" provides for convenient/direct access to the trigger group for all sorts of nasty stuff found in nature. ( I once had a danged acorn fall out as I removed the trigger group from the stock one time
)
Don't get me wrong here.... I prefer to be with nature, as long as nature stays outa my rifle innards.....lol
Note: Someone out there might have a "plug" designed for this very reason, but am uncertain. the Fulton Armory web page may yield results in regards to this.
3. Expensive. Too much for my budget to handle, and much more $$ as compared to what I have invested in my pile of GI synthetics. I have found Norinco M14S rifles that cost me less.
4. I have no issues with a decent GI synthetic stock, as it just feels right for this type of rifle. As mentioned already..... I would really like to get my mitts on one of the newer SAI plastic stocks so that I can weigh it up against my GI synthetics, as well as a few other comparisons.
5. These same Sage stocks can be used in tandem with several different types of receiver mounts. (Ie..... "over the bolt"). I have personally used a Bassett, ARMS #18, and a Smith Enterprise Inc (SEI) mount along with the Sage stock, and without any issues.
6. As mentioned, the term M1A1 is not the correct nomenclature, but is very close to a model of M1A. This model is referred by SAI as the M1A-A1 Bush rifle, and is trade marked by them, along with the term "M1A".... as of 1973.They should not to be confused with the old government run Springfield Armory, as they produced M14 service rifles, along with GI synthetic stocks in tandem with another company called the General Tire And Rubber CO.
7. Some examples of my favorite rifle
At top = A SAI M1A-A1 Bush rifle
Other = A custom built M14S "Tanker" (Norinco receiver)
note: The reciever mount installed on the M14S = ARMS #18 older "split rail" mount.
I fill the selector lever holes myself......
I estimate the total cost for both stocks to be at $30.00.... to include fill work, prep work, and paint, along with the hand guards plus hand guard clips.
For comparison, the following is an unmodified GI synthetic stock installed on my LRB Arms M14SA Tanker
BTW..... I hope that I'm not coming off as a "know it all" in any way. I was very much into this type of rifle before I got into the internet, and have learned a few mistakes the hard and expensive way. (I hunt with mine)
Most anything M1A/M14 related will cost a few $$, so it is well worth the time for researching things prior to breakin out the wallet imo.
Food for thought at the very least
11B