Well, THERE'S an old thread! Fortunately, Hotmail alerted me to it...
Alas, I don't know who made those holsters or the others used on, "The Lost World". We fans never had much rapport with the prop people, although they did eventually sell all of the guns, including some rubber models.
Roxton's rifle was said to be a .416 Rigby, but when I queried if it was a genuine Rigby, the prop guy, who wasn't an armorer, couldn't say.
The nickled Webley MK VI's with white grips were used by Roxton in the last couple of seasons, although he also used the .45 auto, as late as the final show, the Third Season cliffhanger. If you saw that, you may recall that he had it in his hand as he put his arm around Marguerite while they were fleeing the Spaniards, who thought that he was his ancestor, an Elizabethan "sea dog".
I was able to get good views of the prop guns, and Marguerite had an Iver Johnson copy of the S&W hammerless revolver much of the time. She also probably had a hammerless Webley a time or two, and I think an actual S&W New Departure Safety Hammerlss. In one scene, where she was seized by Druids before she coul fire, the had a Webley MK. III .38, with a conventional hammer. It semed to depend on what the prop house had on a given day.
HOwever, Ned Malone and Roxton had the .45 autos, Roxton also had the Webleys, and Prof. Challenger wore a Colt .45 SAA or Italian copies. In one case, it was a Ruger Blackhawk. If you see the episode, "Finn", look carefully when Finn holds him up and he passes the gun to her. He later rescued her from her plight, and she returned to the Treehouse with him and the Roxtons, after killing her betrayer with her nasty little crossbow.
The holsters were very stylish, and looked much like the old Bianchi flap holster, I think Model 16. I have read that Hellwig makes such rigs. The series was filmed in Australia, so that seems likely as the source for the holsters.
Some years ago, I tried to learn who had made the knife in the "Crocodile Dundee films. I did get an answer, but not a very satisfactory one. A woman who answered said that the star had the blade made by some man he knew, and the handle by another. If they had had that info made available to their PR people, I could have goten the movies some nice press in US knife magazine,s for which I write. I also wanted very much to get a story done on the "Lost World" guns, but again the producewrs didn't seem to care. They may really have wanted to avoid much gun-oriented covereage, lest it upset liberals in the industry. I was able to indentify a few knives on, "Lost World", though.
I'm sorry that I can't give a better answer. That show has a VERY loyal fan base in some 14 countries, and I think it is stiill being shown in Eastern Europe. We have members on a fan board who see it in Serbia, Austria, the Czech Republic, The Netherlands, and Latvia, among other countries. The chemistry between the cast was wondewrful to behold, and that and the high production standards raised, "Lost World" well above most syndicated TV sseries. I very much miss it.
That said, the Fourth Season was going a little too far off the track I wanted, according to info released by the Executive Writers, Judith and Garfield Reeves-Stevens. They "assist" William Shatner in his "STar Trek" books, and are big "Trek" fans, and they wanted to send Challenger to Mars and some other far-out stuff. There is a good chance that Finn, one of my favorite characters, wouldn't have survived that season, had it come to pass.
This is far you asked, but that show,is the only "fandom" in which I've ever been involved, and I sensed that you might also be a fan.
Now,about the cast and what wonderful people they are: We have a fan board member who broke his neck in a swimming accident while visiting Australia. When we got the word, Michael Sinelnikoff (Prof. Summerlee in the First Season) and Jennifer O'Dell (Veronica) personally telephoned him, and Rachel Blakely, who played Marguerite, actually DROVE an hour from her home to visit this guy in hospital in Brisbane! Thankfully, he seems to be recovering well, and I pray that he will regain full use of his body. That visit from Ms. Blakely thrilled him, of course, and was so kind of her, especially as she is now busy filming a new series, where she plays the mom of some teens in a family situation comedy. ("Mortified", not seen in the USA.)
The actors didn't know zip about guns,and weren't able to answer questions about them at the conventions, so that won't get the answer you wanted. I tried.
My computer is malfunctioning in typing and some of the above may be misspelled. I can't correct it.