First let me attest to what I am sure you already know: "Tasty sweet ride, bro!"
Had I not just purchased this baby in February, I would certainly have taken a serious look at yours. Timing is everything. But you are correct in saying that a Valk is not for everyone. As could be said about most bikes - including our beloved Wings. And, as for parts, unfortunately the Valk was not produced for a long run and thus the limited availability of parts. That's why you want to be careful to get one that's been babied.
I sense your friend will benefit from that fact. Doesn't change the fact that the Valk is one unforgettable ride. And truer to the spirit of the original Wing.