Hi again
@Light air,
Always best to attach a photo to better describe the part you're discussing. I'm not familiar with a teak sliding hatch but have both the hatch cover and hatch boards done in 1/2" acrylic.
Second photo is poor and only shows the edge of the acrylic hatch cover.
If your construct is the same, no reason you couldn't replace the teak with acrylic.
If you've got a hobby woodworking shop, acrylic is great to work with. If not, an acrylic supplier often has a shop to form acrylic for a price.