Can you help to identify these frames, bikes or parts?

Olmo use them as well:

@HHC, what about this: http://www.framebuilding.com/NEWPARTSPAGES/Cast%20Fork%20Crowns.htm

LC14. Lightweight hollow design.
Weight: 140gr. 51.5mm c to c.
30mm. wheel clearance.

S-LC14. Above in stainless steel.

LC32. As above but with 7° rake
built in for straight blades.

Also this: https://big-forest-frameworks.myshopify.com/collections/all/fork-crown-25-4mm

LC14

Appears to be called LC14/LC32, depending on the rake angle (LC14 Degree: 0,
LC32 Degree: 7)

Rychtarski can make that fork for you, got one on mine