There aren't many sway back jacks on the market. The Case/Bose has the best lines, without any doubt. If you're OK with the short-ish size, you surely can find a jack (2 blade) or Gent (one blade) with handle covers that you like. IMO, the best looking ones are the chestnut bone (in non-stainless CV steel), the canyon jigged chestnut bone (stainless), and the pocket worn red Gent (single blade). The stag ones are nice too (but expensive), but it can be hard to find one with stag you like, and ordering one sight-unseen online can be a coin flip.
Apart from that, the only currently made SBJ is the #47 Hayn' Helper by Great Eastern Cutlery. Available with 1 blade or 2. However, these are much, much larger knives, and the large blade is more of a sheepsfoot than a wharncliffe, so the lines aren't nearly as sexy. Plus, they're only available with plastic handles, and without bolsters (so far, anyway). An orange or glow-in-the-dark acrylic one might pass in an office environment, but the black probably won't. And although they're certainly not "offensive" in appearance, they're not as classy or inoffensive as a knife with bone, antler, or wood handles.
As Stitch suggested above, the GEC #62 is a very nice wharncliffe knife as well. You can find them in 2 spring 3 blade models (whittler) or single spring 2 blade models (congress). The #61 half congress is a bit shorter, but not quite as streamlined. Neither are SBJ,s but both have nice lines, straight blades, and are very pocketable. But either version will likely cost you $90-130, so that's going over what you'd probably consider "entry level".
