Yet to be actually cut, and I may abandon this idea, but here are photos of a board a leg extender joint for a parsons table.
The table I have is 18" tall, but I'd prefer it to be 24" tall to make a more useful side table. I'd have to be able to remove the legs to cut this on the bottom of them. Debating on whether to use the same wood or a contrasting wood to emphasis these "feet" and the joint. Walnut perhaps which I have some of.
I've come up with a similar joint for extending dowels and it got used to good effect on a couple of student projects. That one is likely already posted here.
4D