We have a line of sight posts made specifically for the Magpul MBUS PRO steel flip up sights. These include different shapes, paint colors and with or without tritium dots. Look on our website under Firearm Sights / Magpul MBUS PRO Sight Posts.
Click Here for More Info:
https://www.blitzkriegcomponents.com/magpul-mbus-pro-sight-posts.html