I think the new photo is slightly larger but that makes the differences bigger too.

Sometimes the 5% of differences can make a lot of difference to the eye. A longer barrel and a slightly slimmer fore-end perhaps shorter fore-end (?) and less curve to the grip would do most of it.

At least for those interested in a Rigby amd can't source vintage models, there is now a source of newly made ones for hunters to buy and use.