Indeed it is, even though it seems almost impossible to find. At the same time, your scan suggests that it was not an executive or novelty item with a very small production run, but simply a variant of the 9603 with seemingly equal diffusion on the market.
The reason why this particular pencil (which also won some design award in Germany back in the day) is in fact so rare is completely obscure to me. I mean, I found a pair of 9603 in a drawer of an office-supplies shop once: why haven’t I been able to have a similar strike of luck with the round relative?
Any further information might be appreciated. Also, if anyone here has spare 9604’s to sell, or is not happy with his/her specimen, I think there are at least two people on this thread awaiting for a DM, and ready to talk about selling or trading…
)