One of the splits was so bad that i pulled the 2 pieces apart, doweled them and epoxied it all back together. the other 2 cracks that werent as bad i cut a "V" into the wood along the crack, and pulled the wood apart just enough to get the resin down in the crack. I then added my saw dust and resin once that was tacky enough to take the clamp off. I sanded everything once cured, tacked the stock with mineral spirits, and put several coats of oil finish on it.
Take you stock off when you go to choose your wood to make the dust to add to your resin. I took mine to a fine woodworking shop and looked through their carving/turning blocks and found one where the tones in the wood matched the stock pretty good.
Im not sure what the name of the tool is but i have a hand tool that cuts a V into the wood for carving. I used this instead of a knife because i was worried that the knife would follow the grain and create a larger cut than i wanted. Might have worried to much but it worked for me. Like i said i wish i had pics to share but i hope this helps. Good luck.