Rear side window non-standard aperture????

Hi,

Currently trying to replace sliding windows with new fixed tinted ones from masai4x4, that fit standard aperture 1057x427mm. On removing the old windows I found the aperture to be 1105x420mm and the old windows also had no fixing rivets and only secured in by the rubbers.

Any ideas whether this size was fitted to any land rovers past or present? Unfortunately, I now have a hole that I can't find any glass for

Thanks,
Aaron

It used to be very popular to convert van back Defenders in to pretend county station wagons as they fetched a greater price. No idea how many after market windows were available to satisfy this demand. Or, if they were different sizes.
It might be original, I don't know if LR put different sizes in.