Is this SG M1 Carbine Stock Authentic?

Need some advice on authenticity and value of this stock. This was a comparatively cheap ebay pick-up. So if not authentic, then no big deal. Just a shooter stock.

If real, I will seriously consider professional fix of the recoil plate area. Could this be a stock that was sent to reject pile and eventually stashed away or just a new manufactured copy? Looks too good!
If a copy, they did their homework.

Please provide reasons for your opinion, as I am trying expand my knowledge of what to look for. If you have a fake like this, please post pics. If a reproduction, has to be more than one out there.

The cartouches appear to be correct, the stock appears never used military new and metal does not appear to have been put on the furniture. However, no “P” cartouche is present (could it be because of the small chip near the recoil plate and this was sent to the reject pile). If a fake/reproduction should of at least had a “P” stamped on it.

I used the following reference books for my evaluation:
Reisch’s book U.S. M1 Carbines, Wartime Production, 2007 edition
Ruth’s book WAR BABY!, 2006 edition

Here is what I know: It is a Rock-Ola supplied High wood carbine stock, with a chip out in the recoil plate area. The recoil plate area behind the receiver has a horse shoe cutout is this style consistent with the Rock-Ola stock?

- SG and Cross cannon cartouches match Reisch’s book, page 123, fig 4-8L and Ruth’s book, page, 315, fig 324, center row far right cannon cartouche.

- RSG/105B (Rock-Ola) stamped in sling cut out area MOSTLY matches description in Ruth’s book, page 435, Stock Group, sub-heading Stock, Type A, Variation 4 (in use during late production). Page 289, bottom of page describes Variation 4 as being a Low wood M1 carbine stock.
This is a discrepancy with high wood stock I have.

Is it possible that some High wood Rock-Ola contract stocks made it out with the RSG/105B stamp (i.e. transition period)??

Thanks in advance for your help. Let me know if you need more pictures.

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