What about very fine wood shavings from a board plane grinder for use in a dust bath recipe or maybe just by itself?
Wood shavings will work as part of a mixture (Our mixture is 4/3/2/1 DE/Wood Ash/Fine Dirt/Wood Shavings). However, when used alone, wood shavings are comparable to chickens rolling in their own feathers.
Reference:
Scholz, B., Urselmans, S., Kjaer, J.B. and Schrader, L. (2010). Food, wood, or plastic as substrates for dustbathing and foraging in laying hens: A preference test. Poultry Science, 89: 1584-1589 DOI: 10.3382/ps.2009-00598
Sanatora, G.S., Vestergaard, K.S., Agger, J.F. and Lawson, L.G. (1995). The relative preferences for feathers, straw, wood-shavings and sand for dustbathing, pecking and scratching in domestic chicks. Applied Animal Behaviour Science, 43: 263-277 DOI: 10.1016/0168-1591(95)00562-7