How bad is the splitting? If the stock is all there (no missing chunks) you can likely make a repair with some epoxy and careful clamping and/or wrapping.
Correct the cause of splitting and refinish the wood to a darker color. My experience with refinishing that Birch has been a spotty success story. The best results I have found is to use dye, not stain.
There are a couple of guys here who are knowledgeable in this area, Gnoagggh is one that comes to mind, Maybe if you could get a pic of the stock on here, you would get input on whether it is salvageable.