Found a site that sold Vans Ultracush insoles and put them in my Sk8 Hi's. Such a good decision. The difference in thickness is striking. Link in the comments for the website
FOOTSOULS for Authentic, Era, and Slip On Vans – FEEL YOUR SOUL
Pace Thin Insoles Replacement Top Covers | Tread Labs - Tread Labs
FOOTSOULS for Old Skool and SK8-HI Vans – FEEL YOUR SOUL
Insolesgeeks replacement Pop/ultracush insoles a review. : r/Vans
Replacement Vans Insoles IGS-8527 | INSOLESGEEKS
FOOTSOULS for Authentic, Era, and Slip On Vans – FEEL YOUR SOUL