I recently purchased a PCP rifle and am using a high pressure SCUBA tank for fills. There is a place a little east of me that will fill SCBA tanks that I found after buying my SCUBA tank. Their was at least one place to fill SCBA tanks in Denver that I knew of but they have since closed. The other person I know that has a PCP rifle is looking at using a nitrogen setup since the Denver shop closed. I have also thought about just getting a compressor of my own.