Doing a bit of digging around using the aircraft serial number, this may not be the billed Strikemaster but a T.3 Jet Provost. Some information from Jet Provost Heaven

Jet Provost T.3 XN637 was built by Hunting-Percival at Luton, and after flight tests was declared ready for collection on 31st August 1961. It was ferried from Luton to RAF Shawbury a week later (7th September) where it went to 27MU, for final preparations for RAF service began. On 5th October 1961, XN637 was issued to No 3 Flying Training School (3FTS), based at RAF Leeming in Yorkshire. This Unit had reformed the previous month as a Jet Provost squadron. XN637 remained in service, latterly as aircraft number ’13′, until January 1963 when it returned to RAF Shawbury for storage. It stayed mothballed with 27MU for nearly ten years until November 11th 1972, when it was moved to RAF Kemble for further storage, this time with 5MU. On 14th February 1973 XN637 was officially declared a NEA – Non Effective Airframe, and within a month it had been struck off charge

Here’s a snap of the photo during the display. The serial number on the plane in the photo confirms a Jet Provost (?).

BAC Strikemaster, Old Warden, 2nd August 2009

Recorded on 2nd August 2009, Old Warden, Beds, UK.