Modern Datahand-style keyboard with trackball and trackpoint

svalboard.com

I wouldn’t mind buying a lefty one only for gaming purposes, if it was about $700 cheaper

There's a similar keeb, that released a couple years ago and is a fair bit cheaper (although still not /cheap/): https://www.azeron.eu/.

I can't speak about its quality as I'm not a user, but it might be of interest to you

Why not two trackpoints - one for cursor, one for scrolling ?