Maybe it's me drifting off topic but parts is parts
I took a set of detached wheel arches to my buddy Chad Everett. He's made stainless steel parts on woodies and custom vehicles hot rod fabrication. He suggested a place in the Midwest that he said could extrude a couple of pieces that he could then fashion into shape. Which happens to be the same way Brian W. said he had a eyebrow made in the past.
I contacted TEAE guys just to try and get a listing of owners for a co-operative project. I stopped there as I got tired of dealing with some owners and their, I've got mine attitude plus spares or my cars over insured I'll let them have it if something happens. It's hard selling and dealing with objections. Unless you have a product which sells itself or is the best price it's not much fun. Some guys choose to beat your item up just because... Here's a taste...
400 dollars that's more than I paid for the whole GD car.
Buyer holds a housing out at arms length and says it's heavier than a stock one. Another put the top on the ground and looks down and said the collar for the hold down is 10 degrees off. Or the Tiger email lister saying that the bottom carb flange is too short. Then there's the Norm quote that all real LAT chrome lids have a different part number. So you quickly learn the customer service rule that the customer is always right, and get used to biting your tongue...
I'm only have librarian status here but they did ask me about the side out headers. Of course it was at a meeting and I was nosing into a conversation. I think they could be great if that's your box to check. That being Stock with LAT options. If you take the % of market share argument and apply it to everything you will probably end up making nothing. So I say Bravo to the club for pulling the trigger even if I am not running a header equipped stock car. I see the mission statement of the club as promotion of the marque, brotherhood, and parts development*
Tony the seller is SunbeamAlpineTigerSpares in the UK do different spellings. On the latches again I have not seen them. And the "preferred vendor." was merely a I can't recommend them as I have no experience with them. Seems like the Alpine guys would rather re plate the original ones and beat back together with a stainless steel rod, as you have to tear them apart to re fit them. Lots of things should be made IMHO.
As for the Alger making by seller's it's not always the case. I had a car that they sliced off the entire wing so no gennie dent and Alpine firewall brace on one side....
So after a insane hunt for one a tease by one guy in a, "if you have to ask how much you can't afford it and I won't even give you a price or return your 3 calls after saying I had one available." Then, John Bailey came through with the piece, but it was a lot for a piece of vintage ferrous oxide

Now they are reproduced by the U. K. Co. that sells the latches Tony asked about.
*In no particular order.