Pulse counter for water flow meter?

Hardware
1

I’m looking for a simple way to measure cumulative water flow (gallons) through a pipe and have this appear as an entity in Home Assistant. (This is basically a water sub-metering application, but no need to be revenue grade or include any sort of “smart shutoff” function.)

I have a meter installed (this one) which claims to have a pulse output. Can anyone recommend a device that can basically count the pulses and expose them as a HA entity?

My preference would be Z-wave based, but only thing I’ve been able find is the “Royallo z-wave pulse counter” for $95, but the company’s website (with a webhosting.comcast.net URL) doesn’t even seem stable enough to let me place an order, so I’m just a little skeptical. Any recommendations?

2

There are a few out there, like the Moen Flo which get quite pricey ($350-600 USD) and all have the same fatal flaws: the internal flow components often clog, jam or deteriorate and all of them require a professional plumber to install (another $1,000 USD). Most of them have mixed reviews because of the failure of the internal components, they just don’t seem to last. I investigated this pretty thoroughly and decided I cared less about water flow than to be able to shut it off and went with a handful of Zooz Titans instead for that purpose.