I don't know if I'd recommend it, but if you are absolutely set on having the Thinkpad nipple -- I don't use it, even if I really want the Thinkpad trackpad -- the factory that made the original IBM Model M keyboards is still in business somewhere in Kentucky. IIRC the employees bought it or something when IBM stopped making the things. They offer a nipple keyboard, goes by the name of "Endura Pro". checks Unicomp. That's the remnants in the US of the IBM business; the Chinese Lenovo purchased the laptops and also do the Trackpoint.

I got one like twenty years back, and while the actual buckling-spring keyswitches on the keyboard are pretty much immune to time, I wore out the switches on the mouse buttons, so I don't know if I can give a buy recommendation for the mouse-enabled version (though maybe they improved the switches there). But if you really, really like it, that might be worthwhile for you. Last I looked they were still making them.

checks

They've got a message up saying that a supplier of a component used in that keyboard went under due to COVID so they suspended production. I don't know what the status is on that.

https://www.pckeyboard.com/mm5/merchant.mvc?Screen=CTGY&Category_Code=EnduraPro

NOTICE CONCERNING AVAILABILITY – Unfortunately, we have had to temporarily suspend the sale of the Endura Pro keyboards due to another supply chain shortage. The supplier of one of the flex harnesses had to close their doors during the pandemic. We’ve begun the task of sourcing a new supplier but do not have a definite time frame for when these keyboards will be available again. For our customers with orders already placed, we have enough stock to complete all on order.

Keep in mind that this is a very large, heavy keyboard that you could brain someone with; if you're going to haul it around with a laptop, it's going to be larger and heavier than the laptop. Mentioning it mostly since I figure that you might use it at some location where you could leave the keyboard.