We took a Thorlabs IO-5-1064-HP from a box of miscalleneous optics for KAGRA filter cavity testing (next to Mitsuhashi Roberts linkage experiment, purchased end of FY23).

We put it on a micro tilt adjustment stage and made sure it could be adjusted to the beam height from the Mephisto (72-73 mm). Actually the Faraday isolator that was already there was just put on a pedestal post instead of an adjustment stage, so it is likely that the vertical alignment through the FI was not good, generating a visible higher order mode and causing the improper beam profile.