You might check for old straight videos from the late 70s early 80s that include Jack Wrangler among the cast. Jack Wrangler was THE gay porn icon of the era and very, very gay. But he was asked if he was willing to do porn and in his own film autobiography made just before his death a couple of years ago (smoked too much) he admits that although he'd never had any experience or attraction to women, when it came to pound it home in front of the camera for the first time, he was able to easily get it up and keep it up without a fluffer. He appeared in several straight and bi films.