Without pictures it is impossible to evaluate the stock cracks.
I would not recommend firing any rifle with stock cracks until the cracks have been repaired. Cracks propogate.
However a cracked stock can be fixed. I fixed several cracked stocks with Acura Glass available from Brownell's. Acura Glass is an epoxy glue and I have no doubt that there are a bunch of clear, free flowing epoxy glues that would work just fine. I have found that shops that cater to boats, “Marine Supply Stores” have can upon cans of fantastic high grade epoxy glues. Boat owners have a lot of wood and fiberglass that must be repaired after ramming Great White Whales.
What you want is something that will flow into the crack. Just a thin layer of this stuff is actually stronger than the wood.
I will apply masking tape covered with johnson’s paste wax around the crack. With tape you can peel the mess off later and epoxy won’t adhere to the paste wax. Just don’t get the paste wax in the crack. Then spread the crack and try to get the epoxy to wick into the crack. When the crack is well coated, I will clamp the part reasonable tight. I don’t want all the glue to ooze out, but I want a glue joint that is hard to find.
When the stuff cures to a gummy level, peel the tape off, scrape off excess glue with a plastic sharp edge. If you wait too long it will take a dremel tool to grind the epoxy away.
Depending on where the crack is located, this should work.
I had a Garand stock that a slamfire incident cracked the stock from the lower ferrule through the pistol grip. It was my first and most crude glue job. But it worked. Then I decided to use that stock to learn how to route all the wood and glass bed a Garand action. While my bedding job looks like extra crunchy peanut butter, the crack and the bedding job worked fine. Shot good scores.
Then I bought a nice stock and had that bedded by a pro.
I bought a bunch of M1903A3 stock reinforcing bolts. These look like long thin brass screws without a head. I think they were drilled into the stock. I have not used them yet, but something like that might help reinforce a glue joint.
Don't dump or damage the original stock until you get that replacement stock in hand. My experience with aftermarket replacement stocks is that they take hours upon hours of fitting work.
You had best be darn good with chisels, rasps, sandpaper, drills and bedding tools. You may decide early that repairing the old stock is the best way to go.