Paddy. You might well be able to obtain an airline with rotating tightening caps on each end.
I would imagine that most airbrush suppliers should be able to supply one as the thread size is probably an industry standard on many makes of air brush?
My three Badgers have the old thin hoses.
Which leads me on to Badger Spares. Despite Barwell the UK distributor no longer trading I have found a few other places selling Badger spares by just typing in Badger air brush spares suppliers UK as a web search. It depends of course on what spares you might need, but I should think that run of the mill spares like needles, seals and so on might be reasonably easy to get here in the UK.
If push comes to shove, Badger in the US should be able to help, but my experience of emailing their spares/customer service department at least 3 times elicited no responses whatsoever. If this is the norm then I am not impressed !
I have a very old Badger 100XF, an excellent and expensive at the time, little air brush that I bought way back in the 70's that has a cup that locates into the side of the main body. I wanted to buy a new shell with a gravity feed that I hoped would be interchangeable to be able to utilise many of my original air brush parts. Not having the courtesy of a reply from the parent company. I will now be ditching the product altogether and going the Iwata, H&S, Apex or some other quality air brush route. It is a shame really as having been loyal to using the Badger brand for as long as I can remember it is now time as I see it to move to another brand. If they cannot be bothered to respond to me, who else is not being responded to ? Maybe they now just see the home market as being enough ? Back in the 70's and 80's, Badger was aggressively marketing to the UK model maker via their distributor at the time, Morris and Ingram.
Back then I guess they had a wide open market in the UK model maker.
Paasche however never really even bothered with the UK, and is still very popular with American model makers.
Our own excellent and very expensive DeVilbiss Aerograph air brushes were being targeted at the graphic design/art photo retouching market almost exclusively, and it would appear to me that this would to eventually become their Achilles Heel as graphics went more and more onto computers. They eventually made the DeVilbiss Sprite that was a cut down Aerograph with a number of plastic components replacing metal for the model making market. By this time they had already lost out to Badger in the UK.
DeVilbiss still make an Airbrush named the Dagr that appears to be aimed at the custom car painter and is now made in the USA. The UK company itself is still going strong in making commercial spraying equipment that has always been their prime market.