Igus filament is rather expensive. I wonder if one of their regular bushings could be repurposed by heating under pressure?
Igus filament is worth it. All my linear bearings, lead screw nuts, even some ball bearings, fancy bearings for various profiles, flats to take care of thermal expansion instead of PTFE etc... are made with Igus. No play, no noise. They can be made to be integrated in the parts and fit for minimum play. So they are lighter and smaller.
Can be used on stainless steel (many 3D printers are supplied with SS that won't last with ball bearings) , anodized Al, carbon fiber.
Of course heat can and must be used to match the bearing, nut to the parts. You can't get the proper size and finish out of the 3D printer.
"A comical prototype doesn't mean a dumb idea is possible" (Thunderf00t)