Hardware: Remote Outdoor Valve

I’m search a hardware to manage the garden sprinkler.
It should be a battery outdoor valve connected to openhab. In discounters or in the internet a outdoor battery valve with a simple timer costs 10-20 €! (Default “Gardena” Connection)
I’m searching exact this, but instead a timer it should have a wireless connection to openhab. E.g. a esp8266 wlan chip a something else.
I don’t want to build the complete hardware.
Has anyone an idea?
Thanks, Ben

Have a look here: https://sonoff.itead.cc/en/ . You should be able to hook an electronic valve to a sonoff device via a relay.