Your repair looks good Doc - I doubt that you could get a better match than that. Steaming will remove some dents - using a damp towel and hand iron - but it isn't going to raise the serious dents from over the years. Like any used military stock - it's going to have some and they just add character.
If that split is solid (glued) - you might just want to leave it for now and see what happens. It looks like an old repair and probably isn't going to go anywhere. Mising sawdust with glue is fine and used often - but - glues will not take stain and often show up like a sore thumb. If the repair is tight, you might try going to a good home supply store and see if you can find a small container of filler that is used for covering "set" finish nails. It comes in a variety of shades and is actually a soft type of "putty" that you can work into the crack - if the color of it matches the finished wood, it should make the crack less obvious.
I have repaired a number of stocks with toe breaks (originals - civilian style rifles) very similar to your stock. Those stocks usually have a toe plate as well though and the split is caused by the lower butt plate screw and the wood shrinkage over the years. I've cut the damaged portion off and grafted on repair wood - always try to match grain - and although it is a repair, it made the rifle functional again without the fear of it breaking off. I do't think that your's is that bad though.
I'm interested in hearing how you like it once you "fire her up". I have a feeling that you are gong to love it as they can be a lot of fun . . . for one of those new fangled cartridge guns!
Looking good - hope you'll post some more photos of it! Thanks!
If a pair of '51 Navies were good enough for Billy Hickok, then a single Navy on my right hip is good enough for me . . . besides . . . I'm probably only half as good as he was anyways. Hiram's Rangers Badge #63