Fitting rear parking sensors

[Trax]

Hi. I understand rear parking sensors were optional extra on the 2017 focus ST2.

Can these be fitted aftermarket as ford quality linked to the onboard screen?

I’ve looked at aftermarket versions but I don’t want anything cheap that’s stuck to the dash. Is there a way for these to be intergrated after factor build by ford or elsewhere? 

2017 Focus 2.0T ST-2 26000 miles

Thanks

[alanfp]

I know this is only a partial answer, but....

If you buy a cheap set, you can avoid having anything cheap on show by just relying on the audible signal coming from the loudspeaker that you can hide anywhere you like, out of site.  On previous cars I have found that quite adequate, without needing any display.