Based on this product's specifications, here are some alternatives and similar models
Dust Filter for Lian Li O11 Dynamic XL Side by DEMCiflex, black on black
Summary description:
Replacement dust filter designed by DEMCiflex for the Lian Li O11 Dynamic XL Side chassis. Finished in black on black, it protects internal components from dust while maintaining airflow and is suitable for side-panel mounting. Use it to reduce dust buildup, simplify maintenance and prolong the lifespan of PC components in home or office builds.