Twenty years ago that would have been such an easy one to solve...! Only thing I can recommend is haunting second-hand shops and the like - theres a place in Reading near the railway station that has all kinds of SF-related items (including an Airwolf colouring book!) and which has a collection of similar VHS tapes; unfortunately I don't know the name of the place as I've only been in there once.
"The power of bakers, the power of artists; even the power of witches! It must be a power given by God... sometimes we suffer for it."- Ursula, Kikis Delivery Service.