I think you're looking for a rare beast indeed.

Threaded 1 1/8 was never widely adopted for road bikes.

It was a standard that hit a few hybrids for a period. But, by the time it would have hit the hybrid market, they would have all moved from calipers to cantilever/V-Brakes.

I think the best you'll do with those specs is to find an older Hybrid fork (sorry, probably picking up mostly US stock with my searches).

https://www.ebay.com/itm/Touring-For...y/254063193861

Swapping from threaded to threadless 1 1/8" should be easy to do, and would give you a great number of forks to choose from. But, you will also need a headset, spacers, stem, and perhaps handlebars. Nonetheless, it would be a good upgrade.