Eightbore hit the real problems on the head. If the stock is not too bad the real problem is most likely the barrels. If the barrels are pitted inside and or outside they may bee too thin to save. If they are decent then all the rest can be fixed but at a lot of time or money spent to do it right.
I think the triangles are leather glued on to hide a split head repair on the stock. Why that shape and size is a question. If the repair is holding you could inlet new wood into those areas and try to blend it to match. The 12" LOP is another real problem. I hate two inch plus thick recoil pads so only a extension would be an option for me. That would be another blended repair problem.
Might just be much easier and cheaper in the long run to just re-stock it. The fore end has a small area missing but I would try to just repair that area. I may be slow, but fore ends seem to take me as long as butt stocks or longer sometimes. They have a lot of surface area to fit and need to be tight fitting to look and work right.
It all comes down to the barrels for me. If they are useless then the project becomes almost impossible to justify. My wife has pointed out to me that some of the worst projects guns are those I bought off GunBroker.com. Not as a knock against them but that is where some of the roughest guns seem to end up for sale. And I was not only silly enough to buy them all but happy to do so at the time.
