A couple of more sources:
The Pocket Encyclopaedia of World Aircraft in Colour: Fighters, Attack and Training Aircraft, by Kenneth Munson (1966) has color side view and color split top/bottom view of the Vampire T.55, in the colors of the "Ilmasotakoulu (Air War School) of the Ilmavoimien". (What's that, Finland?) Its data block:
Engine: one 3,500 lb.s.t. de Havilland Goblin 35 turbojet
Span 38 ft 0 in. Length 34 ft. 6.5 in. Height 6 ft. 2 in.
Normal take-off weight 12,920 lb.
Max speed 549 mph at 20,000 ft.
Operational ceiling 40,000 ft.
Range with external tanks 853 miles
It says: The RAF trainer version is the T.11 (its FAA counterpart being the Sea Vampire T.22), while the export version is designated T.55.
Warplanes of the World by J.W.R. Taylor, 1966 has an entry for the Vampire with silhouette of the T.11, and gives the following data for the F.B. Mk. 6:
Power: One 3.350 lb.s.t. de Havilland Goblin 3 turbojet
Span 38 ft 0 in Length 30 ft 9 in
Weight empty 7,283 lb. gross 12,390 lb.
Max speed 548 mph at 30,000 ft
Max range 1,220 miles at 350 mph at 30,000 ft.
Armament four 20mm cannon in nose and up to 2,000 lb of bombs or rockets under wings.