All dog tags are no longer being sold by Sapien. Sammy announced this last November (in the Black Friday sales thread, if you want to find his actual announcement).
They’re in the process of moving to a different form of physical items. They haven’t worked out all the details yet. Right now, Dream is having to manually place fields on those physical items, so it’s a longer, more involved process than the tags were.
I’m sure that, when Team Dream have the details worked out, they’ll announce it to us.