It's a Sharon stock, or a pattern for one. There were some parts with it and looking closer at one of the pics and I noticed their unique entry pipe. The rest of the parts look appear to be from TOW, judging by the tags on some of them including the butt plate.
Yes, there was a mix of parts. The entry pipe, the key escutcheon, the L&R triggers with the curved front trigger, the cast steel front sight, the lock bolt escutcheon, the trigger guard, and the toe plates all match the parts in my Sharon half stock Hawken kit. The two upper ramrod pipes appear to be from a Sharon full stock kit. All the parts in the picture below are probably from Sharon.
The butt plate and underrib have TOTW stickers on them as you noted. The butt plate appears to be Track's Bridger Hawken butt plate and won't fit the stock cutouts.
The challenge for whoever bought this will be coming up with a Sharon breech and tang to fit the tang mortise already cut in the stock.
A person might could make Track's butt plate #
BP-HAWK-L-I fit by bending it and/or trimming the stock. And L&R's Model #100 Hawken lock plate will still fit the lock mortise in the stock.
A doable project with the right breech and tang.