Show Image
(http://geekhack.org/attachment.php?attachmentid=37700&d=1303655876&thumb=1)
Yeah, that picture answers everything.
Realforce sets have everything you need for a HHKB except for Right Shift. The Right shift on an HHKB is 1.75x length, with a Profile B. Unfortunately the only key that is the same size is the alternate capslock (Realforce key sets come with two. One windowed, one non-windowed). But capslock is Profile C. So you will need to use a Profile C capslock for your 1.75x Right shift. Is it noticeable? I don't think so. Visually it's not that bad off either.
(http://kb.o2dazone.com/hhkbLightBlue/IMG_7217.jpg)
But that all depends on who you ask.