I like New Found Metals Portlights. The frames are cast in one piece on their less expensive portlights. They might be cast in 2 pieces and welded on the larger, more expensive, portlights, but presumably you would only consider fitting the smaller ones on the hull side.
I have not seen anything to say the New Found Metals portlights are CE certified to be installed in the hull sides (they have CE stickers on them but it does not say for which area, of course, you could ask NFM). They are very strongly made, so I think I would trust them more than the extruded aluminum ones that are CE certified for this location. Here is an article where they are installed in the topsides:
www.semyan.com/HR352/main.htm?p=67It may take close to 2 months to obtain New Found Metals portlights, they seem very slow. I get the impression they make them after you order them, and ordering them down under they are likely to be drop shipped from China.
The smaller portlights use 8mm tempered glass supported by the solid cast frame. They are very high quality, and very heavy (the 317SS is about 6.7kg with the fasteners and outside trim).
They are hard to order, as you need to accurately measure the thickness of the hull first, in order for them to cut the fasteners to the correct length. So you need this measurement in both imperial and metric (unless you want to cut the fasteners yourself, or pay someone to cut them, or make spacers on the inside to suit the fastener length that you order).
It the hull side I like the 317SS, it looks very strong, the glass is only 3 9/16" tall, and has 4 dogs to hold it:
www.newfoundmetals.com/dimension-stainless#317ssNFM sell their own Butyl tape, or Maine Sail in this article:
www.pbase.com/mainecruising/nfm_port_lights&page=1recommends his own:
www.pbase.com/mainecruising/bedit_tape_new_zealandA cheap option that you might want to look at is Whitworths SKU 66212. The size and description looks similar to the NFM portlight of this size, but I have not seen the Whitworths portlight, I think it is most likely a lighter duty portlight than the NFM 414SS:
whitworths.com.au/main_itemdetail.asp?item=66212&search123=portlight&intAbsolutePage=1www.newfoundmetals.com/dimension-stainless#414ssThis Whitworths portlight is cast, so it is probably stronger than anything else on the market other than the NFM portlights and the Man Ship portlights.
I have not seen the Man Ship portlights. I think they are made (in Taiwan) out of extruded sections of metal welded together and polished. They have an option for storm covers:
www.deckhardware.com.au/-categories/hatches_and_ports/man_ship/