Sorry Harvey, but £450 for a jackal is fantasy territory. I sold one last year with the original mount and the earler type SP sight for £120. The metalwork was painted black, which lowered the value somewhat, but, for a good one, I'd say somewhere north of £200, and up to about £280 for a boxed one.
There is a FB group which allows sales (No, contrary to popular belief, it is not completely forbidden), see what they fetch on there.
The South of England has 2 good things, the M1 and the A1. Both will take you to Yorkshire.