Well, the solution was right under my nose all the time.

Argos have a "bench" only 33" deep which is perfect.
http://www.argos.co.uk/static/Produc...er/6090399.htm
£100 from Argos but I was fortunate enough to do a search on ebay and found the same bench for sale for a starting bid of 99p (£16 p&p) from a retail seller. Placed my bid and waited a week. No one else bid so I got it for the 99p + £16 p&p.

Seller was bargainsdirect01. Excellent service. Auction ended Wednesday evening and item arrived Friday morning. Unfortunately they had got their tickets mixed up and had sent the wrong item. They replied to my email within 10 minutes, arranged for collection that afternoon and the proper item arrived this morning (would have been earlier 'cept for the weekend).
Was concerned I may have been buying a duffer but item is new, the external box had clearly been resealed but the internal boxes which housed the glass were unopened so unit can't have ever been put together before. Makes a change for me to bag a bargain.