I pass on the non OEM one but I do have a very good Seat reversible one which is carpet one side, rubber on the other. The rubber side things stick to it so you get no movement of things sliding around in the boot which I was pestered with. The chiller box would bash onto the rear light cover which would drop off in the road as the tailgate lifted. Happended about three times. The mat silicone rubber side up, everything is pretty stuck to it. It is expensive but treated the car since I got fed up clipping the rear light cover back on and hearing the chiller box slide about in the boot. Horton's sell those if you cant get to a main
dealer to pick one up.
Seat Part Number: 575061201A
Think it fits all
Ateca's apart from the 4x4 with variable boot height. Mines standard 4x4 with spare.
Only accessory I bought for it

. Not into sticky bits for the dash etc.