Where to buy in line check valve?

[leem60]

I have a Aquamist 1s and would like to know if anyone can recommend where to purchase the inline check valve for my Supercharged Frontier. I moved the nozzle closer to the SC and it is siphoning water out of the system due to the vacuum it creates. I'm having a hard time locating a dealer to buy the check valve. I'm in Arizona but don't mind buying it from out of state.

Thanks,
Mike