Currently on sale on eBay - item 270362172614 - a Bedford VAL as used in 'The Italian Job' (although that had a Harrington body rather than a Duple). It would make one cool conversion, and cheap too.
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi21.ebayimg.com%2F07%2Fi%2F001%2F1f%2Fcf%2F8fc0_12.JPG&hash=40da9017d490f256045ce457816982ba7240b314)
Jeremy