I found those on DigiKey by going into connectors > circular connectors > circular connector contacts, then filtering by pin size (2mm, though I would also look for Size 12 contacts, since those should be 2.05mm, well within tolerances) and pin gender. I usually filter by “in stock only” first, but I don’t remember if I did or not in that search.
Now that is helpful; I've known about DigiKey's parametric search function for a long time. However, look at the bewildering array of stuff you're faced with here: Circular Connectors has 2,754,014 items; Circular Connector Contacts narrows it to 5,775. Filtering on 2mm and in stock winnows it down to a manageable 70 items. But without knowing what to search for it's a jungle out there.
Digikey’s parametric search is, overall, the best parametric search in the industry, and by a pretty big margin IMHO. (Others occasionally do better in some specific way or parameter, but in the totality, only Mouser comes close, and it’s still a clear second place if you ask me.) But yes, you still need to spend some time familiarizing yourself with the taxonomy and the parameters. I’ve been relying on digikey’s taxonomy and parameters for years now, and I still sometimes end up in the wrong place. Nonetheless, I am so much more proficient on their website than any other distributor’s, so they are hands-down the first place I look for things.
Another gold star for DigiKey is how they handle error reports: they always respond, and most of the time they fix the error right away. On rare occasions it’s taken a bit of back-and-forth when they’ve misunderstood the problem, but in the end they come around.
In a way, it’s shocking how bad many distributors’ and manufacturers’ parametric searches are. They often have decent taxonomies, but just terrible parametric searches. In some there’s good data but terrible user interfaces. In others the user interface is fine, but the data quality renders the UI pointless. And others have terrible UIs and terrible data. And the worst have no parametric searches at all.

(One that truly baffles me is Conrad: they have reasonably good metadata in many categories. But many of the parameters are not available for filtering and don’t appear in the results tables so you can’t even sort by them. Why do the data entry if you don’t let people use it to find stuff?!?)
So thanks for that; I've decided that unless I find some inexpensive ready-made solution I'm going to go ahead and make my own here. Turns out that ordinary copper 12 AWG solid wire is the perfect size, and there's lots of that here. Sure it's soft, but with care it should work well for this application. Now I just need to find some suitable plastic tubing.
Indeed, non-metric contact pin sizes are just the diameter of that AWG solid wire. So indeed a size 12 pin is the same diameter as 12 AWG solid wire!