I'm switching from a 240v compressor to a 12volt unit with my hookah unit. The regulator I have is a Scuba Max XLT2002. The inlet valve cracks at about 50psi which is no problem with the 240v compressor but my new set up is a Thomas diaphragm pump with a working pressure of 30psi. The pump is the same unit as in one of the bought hookahs as is the regulator. I know you can just alter the spring to open at lower pressures but I'm reluctant to just jump in. I have found cutaway diagrams and part lists but no actual instructions.
I also took the unit to the Huskisson Dive shop but the "specialist" had never seen one of the regulators before and went weird when told it was for a hookah! These regulators are made in Taiwan by the thousands and sold under various brand names.
I have two choices it seems.

Dive in and pull the unit apart and experiment, finding a suitable spring might be a problem.

Or buy a new one and on sell this one on eBay while its still perfect. I have seen a site online that sells regs with opening pressures of 25psi for $69 US but naturally can't find the same site again! Postage from the states is about $18 so buying new is still cheaper than getting a service at a dive shop.
Anyone have a link for me? Any ideas?