The 24F is still on the Savage site, and is still made. The problem is the POS plastic furniture on them. I really really want a .30-30 / 12 ga with WOOD - man oh man.
Hopefully 12 guage and 223 combo maybe or even a 308?
You're in luck at least as far as the .223 is concerned. Several distributors and a few shops have the Remington Spartan (Baikal) SPR 94 O/U combo gun with a 12 ga on top and a .223 Rem on BOTTOM. It's a little rough, but pretty cool.
http://www.remington.com/products/firearms/combination_shotgun-Rifle/SPR94_specs.asp
Baikal makes many other combinations besides those 3, but those are the only 3 that Remington imports and slaps the Spartan name on. You might be able to get other combinations through a special import - shouldn't be hard to import single shots.
Here are the combo guns I have (three 2-bbl combos and one single-bbl combo):
1. (aformentioned) Baikal SPR, 12 ga/ .223 Rem
2. Savage 24 F, .22lr / 20 ga
3. CZ/Springfield M6 Scout, .22lr / .410 bore
4. NEF SB1 "Survivor", rifle .45 colt / .410 bore bbl (one bbl)
Edit: I don't see the 24 F now on Savage's website either now that you mention it. If they HAVE come off the site and been discontinued, then this is a VERY recent development.