Tabletop-Art gives your Chaos troops some new heraldry to march to with the release of their new Banner Set 4 over in their webshop. These could be used, obviously, for any sort of banner-bearer, but also attached to vehicles or war machines that you wanted to add a bit of flashiness to.
From the release:
New Banner Set available:
The set includes 2x different banners made in Resin. Scale: 28-30mm