Scott, since they made a very large percentage of the guns y'all are listing. Only a handful of names had the ability to make an entire gun in house. If Scott (or Webley & Scott) didn't make the entire gun for the name then they provided a huge number of actions and barrels for the trade to finish. And that seems to include a lot of the London trade.

When an old man dies a library burns to the ground. (Old African proverb)