Dia Compe do some too - a bit longer. Otherwise search for bikit mudguard mounts on eBay. Those also work for some solid axles - bigger hole. Plus they are thinner and (at least used to be) cheap. Or get some flat steel or aluminium and cut/drill/mill to your heart’s content.
Expander bung underneath and bolt in? (e.g. SKS Shockblade kit and bodge a bracket) Then PDW eyelets at the bottom?