Take a look at tenkeyless keyboards, then. They don't have the numpad, but keep everything else the same as a full-size (104 key) keyboard. For example, the Realforce 87U is a tenkeyless keyboard with Topre keyswitches (same as the HHKB): http://elitekeyboards.com/products.php?sub=topre_keyboards,r...
Or if you want Cherry (rather than Topre) switches, the Filco Majestouch 2 Tenkeyless is a good option: http://www.diatec.co.jp/en/det.php?prod_c=765
Or if you want to save a bit more space by pushing the keys at the far right and on the top row up against the main section of the keyboard, there's the Noppoo Choc Mini: http://www.amazon.com/Noppoo-Mechanical-Gaming-Keyboard-Swit...
The Leopold looks like a worthy alternative to the HHKB, with a very similar vibe, especially as they allow you to swap Ctrl / CapsLock via a dip-switch (I wonder if they sell alternate keycaps with the labels swapped too). It seems to occupy a nice price middle-ground between the HHKB Lite (2) and the HHKB Pro, and has nicer switches than the HHKB Lite (to tell the truth, I don't mind the HHKB Lite's feel, but it's a little on the cheap-n-cheerful end)...
[The only significant difference in layout seems to be the "\" key.]
I was looking into this a few days and it doesn't look like Leopold doesn't sell extra single keycaps or sets. You can browse their site (Korean) to confirm http://leopold.co.kr/
I've read that they're rebranded Filco keyboards. The worst thing about the CM Storm is the key cap font, which is just really ugly. And because they're printed on, my wasd keys are fading after 2 years of use.
This is definitely not true. Filco build quality is unmatched in terms of Cherry switch keyboards, although Ducky is getting close these days. The CM Storm keyboards are of noticeably poorer build quality, although you do save some money in return.
Personally, I would get the Filco, since a keyboard isn't something you have to regularly replace. It's worth spending the money on the best keyboard you can get. Same goes for your desk, chair, headphones, and laptop bag. People were shocked at first when I dropped a lot of money on these things, but I'm still using them 5+ years later, where many others have had to buy new ones (especially bags and headphones).
That's why I just switched to using the mouse with my left hand, even though I am right handed.
[1] http://elitekeyboards.com/products.php?sub=leopold,compact&p...