Of the ones that are sensibly priced and look like they won't generate false alarms, the Pyronix XD10TT-AM is the best match I've found so far:
https://www.securitywarehouse.co.uk/catalog/pyronix-xd10ttam-high-security-outdoor-detector-p-3912.html
12V, dual PIR + microwave, pet (wildlife) immune - the spec seems to tick all the buttons.
I plan to use it for a combination of a driveway chime, to activate a flood light (in combination with a photocell), and as in input to start CCTV recording.
It has an (optional) wall bracket that looks well worth getting too.