Blu-ray is finally coming!
https://bloody-disgusting.com/home-video/3487858/1982-sci-fi-horror-film-xtro-finally-coming-blu-ray/
Second Sight Films in the UK is releasing a (limited edition) region-free Blu-ray of Xtro, packed with special features. It will have reversible art a la Scream Factory, a "softcover book" and the soundtrack CD.
This is the first I've heard of the film, but it looks interesting.