We sometimes offer used parts when we receive them as a return, so our stock of these used parts depends entirely on if we receive any returns of the part from other customers. Due to this, we cannot say for sure if or when we will have more stock of a used part. Your best bet would be to continue checking the item page periodically to see if the "out of stock" status changes to "in stock", or consider the new & unused version of the part, found here:
https://www.monsterscooterparts.com/mobility/mobility-brands/hoveround/hoveroundmpv5/4-key-vsi-joystick-controller-hoveround-mpv5.html