Window in shower

We're about to renovate our bathroom and I would like to move the shower to a wall with a window in it. The window extends across the width of the wall at shoulder height so it may get some spray from the shower. When I read overseas web sites they seem to use PVC or vinyl windows in showers but I haven't found these types of windows in Australia when hunting on the internet. The current window will need to be replaced as it is an aluminium sliding window with a track that would fill with water. What is the best type of window to install for this situation? Also, will a tile sill be sufficient or is it worth installing a granite sill to match the vanity?

We have a long window - rectangular - just above head level. A nice shelf there too for things ...

We can't see the "sill" - but it is tiled.

If it is shoulder/head level then it might not need a curtain etc - just be cathedral type glass imo. Might be quite nice. But definitely needs waterproofing imo.

Any commercial Aluminium section would work (they're flat and water although it would sit on the sill would not get "trapped" on it)

But thats only if youre happy with a fixed panel - if you wanted an openable window you'll struggle