Just came from the library after looking for Reuben Turvey as they have a free connection there, just did a search for 17th lancers and up you came!
any way:- John Turvey and Ann Lacy were married 24 May 1807 at St Peters Worcester ( seems to have been a bolt hole for marriages for the Turvey family when things are rough going ).
George son of John & Ann was Bap. 7 sep.1807 St Andrews Pershore
There's a George & Mary Davis married 30 Sep. 1840 St Albans Worcester, whether this is the same one I'm not sure.
So Reuben's father John may have been a soldier, or lived in one of the villages on the Evesham side as they tended to use St Andrews more the the Abbey, Holy Cross.
There was a John in 1881 who was a Chelsea Pensioner living in the hospital there but he was born 1836, too late to be the father.
Hope you find something I've been looking for hin for the last 10 years as well
Mike Turvey