can anyone suggest a decent one?

Are you looking for something with a gauge to mount on the dash to monitor pressure? Or a mechanics pressure tester?

[2015 Z Force 800 53/Trail EPS]

I believe he wants one to mount in/on the dash to monitor. I only know this-it has to have an electronic sending unit, not an actual tubing. From experience...you don't want that on an off-road machine. It will break at some point.
For me I wouldn't mind a round two-gauge bracket mounted below the dash-one oil pressure and one actual coolant temperature. Just wouldn't want to cut big 2" holes in the dash. Also wouldn't mind smaller square digital displays stuck to the dash surface as long as they looked nice. The challenge..at least a small one...is finding and/or adapting a sending unit to the metric port. Mayne it won't be a challenge at all. I would want to keep the OE light though so would have to plumb-in a T or Y so you could use the OE switch.