That is interesting information and adds more to the picture I must say. The rifle may well be entirely original. I suppose the hood might be one that was taken from the production line before the two holes were drilled and modified as you see it now?
I'm sure you know, but this rifle was rifled and sighted for MkVI ball, so unless you can find some old loaded cartridges, the 215gr. Woodleigh bullets are your best option. Seeing as you have a nice bore there, maybe wise to get the right sort of powder and loading to preserve the rifling as far as possible - as well as just finding out what the rifle is really capable of accuracy-wise.
If it was mine I would digging out as much of its history as could be found by retracing owners etc.