Fender Flares
Very few people make fender flares for the Astro/Safari vans.
Here is one https://s60.website-secured.com/~customva/catalog/index.php?main_page=index&cPath=83 (also offers wiper cowls and visors as well)
https://www.realtruck.com/fender-flares/chevy/astro/ says they have a set, but I haven't personally tried them, and not really sure they would fit. They are cheap though.
Xenon 10570 - Street Cobra Style Front and Rear Fender Flares Kit http://amzn.to/2iPOQAD
While I would never order from the super shady company CarID(myself and others have had a horribly shady experiences with them, you have been warned), they do sell the same kit.(I won't link them here because they suck).
1985-1994 QMI 146001 Polished Fender Trim, Full Arch, 2" Wide, 4 Piece Set
1995-2005 QMI 146002 Polished Fender Trim, Full Arch, 2" Wide, 4 Piece Set
1995-2005 QMI 146003 Polished Fender Trim, 1/2 Arch, 2" Wide, W/ Cladding, 4 Piece Set
EZflares.com Universal fit rubber lip, increase the fender width 2"