Patio Door Handle Cap (Rectangular)

Replacement push fit rectangular cap for patio door handle (make and model unknown). The overall dimensions are approximately 52mm x 11mm by 17mm high. There are two versions included: upper and lower cap. The photo shows the original (black) versus the 3D printed part (white).

There's also an elliptical cap for the same type of door here:
http://www.thingiverse.com/thing:2010117