Found a fork on Craigslist which may work:
The stem has a 1" / 25 mm diameter.
-- The stem measures 8 1/16" or 204 mm from the top of the stem to the bottom of the lower bearing race.
-- The width between the fork legs at the bottom (whee the wheel goes) is 199 mm
-- The axle to crown measurement is 37 cm, take or leave a mm or two. Or,
-- It works with a 700 mm wheel, showing 1 cm or 1/2" of clearance above the top of the tire.
-- It was previously on a 56 cm road bike frame.