I'm not sure whether we've had a discussion about that already many years ago,... anyway... putting some work again recently into my keyserver (and setting up a second one in the near future)... I stumbled across my membership file again and with that over the port for SKS reconciliation, which I guess everyone uses 11370 for.
Sure, it's freely configurable, but that argument would also go for http/80.
So would you be interested in having that registered officially at IANA?
It's still free right now; 11371 is already registered for HKP.
I have already done some port registrations at IANA for some protocols in the past so I'm a bit familiar with their procedures and could do some of the work.