Blind end-cap replacement (white) to broken one (transparent). My external part of cap fits into a original internal cap. My another replacement parts for this blinds: https://www.thingiverse.com/thing:3991724 .

Bolt is used only to vertical guide. The bolt is larger due to possibility of printer with 0.4mm extruder and fits only to my external part of cap. Blinds from Leroy Merlin, home improvement hypermarket.

Source FreeCAD files included.