That's a neat rifle. Unless Holland's did it, the H&H mounts along with the shortened stock take most of the collector interest away. Its such a nice rifle and essentially a custom rifle now that I would consider having it restocked to order. It would be still be a neat rifle and as long as you didn't go with some kind of Weatherby or thumbhole stock pattern would be a nice rifle that anyone would appreciate. I would say that if you get a 'name' to restock it, the value would increase more than what its worth now, though probably not enough to recoup the wood/stocking fee.
I've seen some wod additions crafted in England that were almost undetectable from a short distance. I've seen few if any added in the US that were matched as well. Seems to be too many variables from this side, or maybe the Brits just have more experience.