Sensus 620 water meter - read consumption in OpenHAB

I’d like to be able to monitor conventional water meter (Sensus 620) so I know the consumption and if the water is flowing (useful for leak detection). My water meter is Sensus 620 and I found the company also sells HRI sensor that can send pulses when water is being used. The model I think works for me is “Sensus HRI-B4/D10”. The HRI B models seems to support ModBus protocol, but it doesn’t provide USB interface. Has anybody here manage to use the HRI sensors in OpenHAB? How can I connect it to USB and which add-on do I need? Thank you in advance!
User manual:

PS: I found some discussion on DIY approximation sensor however I’m not very technical so not something for me.

Caution; M-bus is not Modbus

Hi, thank you didn’t realise M-Bus is not the same as ModBus, looks like OpenHAB doesn’t provide native M-Bus support…

Yes, I expect you’ll have seen that it crops up here a couple of times without real solution. There is a Wireless M-bus binding (WM-Bus) and it may be that could be enhanced for wired interface too, by someone with right skills.