We don't sell the gasket individually, but you can get replacements directly from 7eye. Their website is https://7eye.com/products/airshield-eyecup-replacement Simply choose the eyecup for your frame. Look on the sidearm for the name of the frame, it is likely either Viento, Ventus, or Churada. If you need further assistance, please email Support@AxonOptics.com