I am not a gunsmith but I do repair musical instruments.
I would gently wedge the crack open and inject #20 CA into the crack with a #26 or 27 hypodermic needle and clamp it.

Stewart-MacDonald sells tinted CA. Their Vintage Amber #20 would be perfect for that stock. Done carefully you would never see the repair and no refinishing would be required.

Music washes away the dust of everyday life
Some people wait a lifetime to meet their favorite hunting and shooting buddy. Mine calls me dad
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