Tiny air gauge

I am looking for the smallest air gauge made for PCP air rifle. I have a couple WIKI analog gauges and and Edgun EDMU digital and have looked at the Huma and Sekhmet. I hate shopping on these sites. Spent a couple of hours looking at specs for the sizes. They don't list them very well. Probably knowing the answer but these just stick out to far from the tube. Has anyone found a better solution. Diameter isn't the problem, it's the thickness! Thanks
 
OK, little more information. I have an Edgun Leshiy 2 so I need a 1/8 BSP thread. This rifle is really simple to change the regulator. I usually run it at about 70 bar but I have it dialed in at 90, 110 and 130. Just fun and Like I said it is easy with the REPR regulator. It is just much easier to leave the gauge attached. Just looking for something like the McMaster but has to be BSP. Thanks