John

I've done quite a bit of restoration & refinishing work, and I would be 
loathe to try restoring those leaves, particularly because they're 
split. You may be able to plane one surface down to good wood, but 
fixing the splits could be a PITA, depending on how bad they are. If you 
can easily close up the splits, and a little planing gets you to good 
wood, you'd probably want to apply veneer to one side or the other to 
replace the missing thickness and, in either case, you'll be faced with 
staining and finishing to match the rest of the table. I know of no way 
to restore the original colour. And there's always a possibility the 
splits will recur. I'd just buy new wood. And salvage what you can from 
the damaged leaves for another project or two.

FWIW
Don