What phono preamp would be good for a Dynavector Karat 17D3?

I don't think this is really a question.  The only way in which the cartridge needs to match the phono preamplifier is in terms of the latter having enough gain to deal with the cartridge output.  Once you're sure of that, it's a matter of your preference and your willingness to spend.

Get yourself a nice SUT and run through the phono input.  No need to get another phono pre as the one in the Cronus magnum is pretty good.

Did not we just address this very recently??????

Parasound JC3+