If you search portholes online, you will see endless variety's in various price ranges. They are not all created equal.
After researching different brands and websites, we knew the portholes we wanted, had to have
A) thick enough glass that a child's foot wouldn't kick through it, and B) we wanted to be able to actually open the portholes. Many online versions are basic simulations and don't open or have double pane glass.
The porthole was the last step in completing this gem! Instead of trying to edge the paint around the porthole, we cut the hole and installed it after the T&G was fully painted for a clean edge to edge installation.
Total Cost: $2,436
Pottery Barn Bunk Bed: $2,999-$3,200