I bought this inline regulator, as featured in HardAir Magazine:
https://hardairmagazine.com/news/interesting-external-pcp-regulator/ I can't find a US based vendor, but there were none when I bought it directly from Ercan - his contact info is at the end of the linked article. I have had great results with the regulator he sold me - it is not externally adjustable, but it is very easy to adjust when not under pressure. It was a very affordable option that allowed me to stick with the tanks and valves I already had but to tether regulated when I want to do so.
If interested, you could reach out to him - he is located in Turkey, and while his English is not perfect, it is far better than my Turkish
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. We were able to communicate with minimal issues and complete the transaction. I paid him through Western Union and he shipped it promptly - and I am very happy with the results. I have no affiliation with him other than being a satisfied customer. This was in 2022.
Do know that the regulator - at least at the design level from when I purchased it about a year ago - did not have vent capability, so that needs to be provided. The video shows it with DIN fittings, but I ordered mine with foster fittings on both ends, as seen in the picture below. To adjust it, I simply unscrew the "cap" with the foster fitting on the left and then I have access to the adjustment screw just like in the video (the cap is basically an adapter to the DIN threads on the body of the regulator. I think it is a great bit of kit - just be sure you have a way to vent it (maybe he has one with a vent now).
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