Personally
I'd treat it to a re-blue and a stock refinish, replace any missing parts and leave it at that. Guns are only collectible these days if they are in original condition, or have been treated specially, such as with professional engraving.
Still, your call, but you may well kick yourself in years to come if the factory original rifles are fetching a couple of hundred quid, while the bubba-ed examples are not worth a penny.
The South of England has 2 good things, the M1 and the A1. Both will take you to Yorkshire.