Hard to find high end keyboard in stock since most keyboard vendors are too small to have expensive stock just sitting on their shelves, so most stuff is sold in group buys so vendors don't order more than they have to.
Here's a list of vendors where you can buy keyboards. I imagine you'll be able to filter by keyboard kits and in-stock at most of them. See if they have anything you like. You can also check out the aftermarket like r/mechmarket on Reddit or Discord servers with trading channels for used keyboards that are ready to ship out.
If you're willing to wait, check out the Interest check and Group buy sections here on Geekhack and you'll see lots of live and upcoming keyboard projects. Really hard to recommend a keyboard to someone, especially an "endgame," if we don't know anything about your needs, preferences and desires.
