i've scored these on a local site for £23-ish - see a2c measurements on the pic. these are the 26" version. they clear a 29er rim with 35c tire and a proper mudguard easily.
maybe you'll find a pair with some patience! (in case it suits your needs, of course)
As soon as I get the delorian running! I don't think they make em anymore and all the sets on ebay are too old for disc mounts.
A Salsa Cromoto would do the job, again though, not common and even the shortest one is a bit longer than the 1x1 fork.
The OG 1x1 fork is a rare combination of short a2c with big tyre clearance.