Have not found anything yet, but, at the risk of stating the obvious, an email to http://nationalarchives.gov.uk/contact/contactform.asp?id=1 should elicit a reply from the National Archives to confirm if they have anything in their files on this incident. From previous experience, they do hold data on most military air crashes for the 1950s – though I I’ve not tracked down the one for Sunderland RN288 yet

The other “obvious” place of contact would be the RAF Museum at http://www.rafmuseum.org.uk/contact-us/enquiry-form.aspx to see what they have in their files