It isn’t obvious from the Germany-based website “Wallpaper from the 70s” whether all of their wallpapers are vintage rolls from the 1970s or if they are just based on designs from that era. Either way, they stock a great selection of wallpapers.
Their stock is arranged by style; Floral, Baroque, Romantic, Glamorous, Surreal and Abstract. The wildest designs are probably to be found in those last two categories, which includes Apollo (pictured here), a pattern I recognise from some curtains we had back in the Seventies! There are more subtle designs then this one though.
There is a gallery section on the website, so you can view most of the patterns in situ which is great for inspiration. The prices of the wallpapers vary a lot depending on the style, but there is a helpful currency converter and they do ship worldwide.
Browse the whole collection at Wallpaper From the 70s.