https://tex.com.tw/collections/keyboard/products/kodachi
The Tex Shinobi isn’t metal, so no help there, but it might have a little more rigidity and still has that Thinkpad layout:
https://tex.com.tw/collections/keyboard/products/shinobi
https://sharktastica.co.uk/wiki?id=ibm88xxultranav
The guy behind these keyboards is making a new 60% with a trackpoint that can be ordered with an aluminum chassis.
https://sharktastica.co.uk/wiki?id=ibm88xxultranav