Maybe reach out to this guy!
https://www.reddit.com/r/Guitar/comments/1gygt0p/mim_fender_stratocaster_hardtail_conversion_and/
Man, you ain't kidding, that's outrageous, it does look like a decent bridge though.
Like all Kahler stuff, it is over engineered. I don't know why you'd need or want fine tuners on a fixed bridge and what problem it solves.
Not sure if you're still looking, but just saw this while looking for something else. Almost three inches wide.
https://www.amazon.com/dp/B09XTMF1Q...d_r=c05e431f-d0a3-4887-a55f-6b90dc0ffb42&th=1
For the cost of a new bridge to span the gap
You can get an ebay body with paint without the cavity
Ebay
search "hardtail strat body"
Dozens
Will do. I usually avoid ebay, I've been using Amazon for years.