I ended up getting a pair of Maxxis Velocita 700x40mm. The entire country is out of Gravelking slicks in 38mm. Actually, all sizes. They are coming out with GK+, so I guess that's why. But having a product switchover in May is a bad idea.
The Maxxis seem nice, they were floppy enough that it was a pain to set them up tubeless, but I finally got them to seat. They have a tread, but it's very minimal. Got to go put some sealant in them and make a front rack for the gravel bike and I'm set.
On edit: looks like my taping job on the front wheel is leaky, so I'm going to run a tube up front. Turns out I had a rack mostly made for this bike, so I just have to finish it today.
Last edited by unterhausen; 05-16-19 at 05:34 AM.