Also, I believe the bus in the photo to be a Samuel Ledgard bus but not sure if that helps anyone
My memory of Samuel Ledgard buses (ee, that dates me!) is that they were two-tone blue, though online photos suggest some were blue and cream - quite similar, apparently, to the nearby Bradford Corporation Transport buses. If the slide is faded, I could possibly also see this as two-tone green, which was the livery of Leeds City Transport.
There are photos of Samuel Ledgard buses at
http://www.sct61.org.uk/index/operator/lg Ours has a straight line below the windows, and no decorative flourish on the side, and bearing in mind the suggestion that it's a Duple body, that seemed to me to leave just two contenders: LRW377 and GVA289. Pictures here:
http://www.sct61.org.uk/lglrw377http://www.sct61.org.uk/lglrw377ahttp://www.sct61.org.uk/lggva289There's a fleet list at
http://www.petergould.co.uk/local_transport_history/fleetlists/ledgard1.htm and according to this, LRW377 was in service 1956-1960 and GVA289 1957-1967.
I can't vouch for the accuracy of any of these sites - and there are quite a few others available. We also need to remember that although Ledgards was a Leeds-based company, they could of course have run excursions to other locations.