Unless you're looking at arranger keyboards, there's no such thing as a studio keyboard versus a stage keyboard. If you don't want to use features like sequencing on stage, then simply don't use them! If the keyboard has the right sound and feel, who cares what other features it has?
Nord doesn't make an arranger keyboard, and none of the main workstation keyboards discussed in the other thread, the Korg M3/M50, Yamaha Motif series or MO6/MO8, and Roland Fantom or Juno series, are arrangers either. All are equally suited for stage and studio use.
If a Nord Stage is out of your price range and weighted keys is a must, Nord has nothing for you. I'd look at the Yamaha MO8 or the Korg M50-88, or if you can find one, the Korg TR-88 (which is now discontinued but might still be in stores).
I wouldn't bother with a computer-based solution; you won't get much cheaper than a keyboard anyway and it means bringing a laptop to gigs (depending on where you play, that could bring up possibility of theft or damage). I did a quick price check on the gear I'd recommend, given that you want a weighted controller, and you'd be looking at a minimum of $1,030 US (priced on zzounds.com). This is for the M-Audio KeyStation Pro 88 controller ($400; M-Audio does have a better one too; this is the cheaper one; I've never played either so I don't know what the quality is), an Edirol UA-25 audio interface ($230; if you're gigging, you want one that's durable; the cheaper audio interfaces are a lot less rugged, although you could obviously buy one anyway), and Native Instruments Kontakt 3 ($400). The audio interface gives you a MIDI connection to your computer and a good audio connection, as well as giving you the 1/4" out so you can run into a DI. Kontakt is a sampler with an extensive library; for the price, nothing beats it.
That would give you great piano sounds, orchestral sounds, and a bit of everything else. You could get some free synths, if you're into synth programming, but depending on your needs, you'd almost certainly want to expand, which would also force you to get some kind of host that supports multiple plugins. This can be a DAW and can be free (GarageBand is not the most ideal but is bundled with Macs nowadays), pretty cheap (Reaper for $50 for their non-commercial license or $225 for their commercial license) or really expensive ($500 for Cubase). Or, you could get a host dedicated to stand-alone performance, like Native Instruments Kore. Kore is great for picking and organizing sounds across all your plugins, but it doesn't do audio or MIDI recording like a DAW would.
Need more sounds? For B3 organ, Native Instruments B4-II; for more various synth sounds, NI again has a lot of good products here; they all tend to be around $200. (Of course, there are other great products out there; I'm just most familiar with NI and find them to be quite cost-effective).
Really, it's obvious that you can spend a ton on a computer-based setup, but you can do so incrementally and you can add to the setup whenever you like instead of spending a lot at once on a workstation and being stuck with what you get. Computer-based setups will give you better-quality sounds because you have more variety and more space for samples. Kontakt 3's library is ~32 GB; you'll never find that much sample data on a workstation today, other than the Oasys. The difference is that Kontakt can stream from disk instead of having everything pre-loaded in memory.
So what do you choose? If all you ever do is play gigs and have no interest in recording your own stuff (recording with your band in the studio is very different since you don't need the gear for that), I'd go with a workstation keyboard; if not, I'd go the laptop route.
