Look, I see that you are a passionate fan, and that's great, but I have no idea why you seem to be so wound up over this topic.
I started this thread for one reason and one reason only, to uncover facts, proof, evidence. So far you haven't been able to provide any of those things. No one is disparaging Shah Safari, no one is saying the Almanac isn't a great book, or anything else.
Bob Gale endorsing the book doesn't mean anything to this conversation though, sorry. Bob's a great guy, who knows an absolute ton of details about these films, but he wasn't the wardrobe stylist. I really doubt amidst shooting BTTF he went over asked MJF if he could take a look at his shirt tag. A great example is Marty's sunglasses, for years and years fans were trying to figure out who made them, and when they asked the Bobs, their answer was that they thought it was some kind of endorsement deal, but they couldn't remember. Then an early draft of the script came out that said they were Porsche sunglasses, but it wasn't until many years later (just within the last few years, in fact) that a fan discovered their actual manufacturer as being Zeiss. Same thing with the vest, go back and look at how many tons of sources inaccurately listed it as being made by North Face, until it's true manufacturer was finally discovered a few years back.
As for it being 30 years old, I own the maroon T-shirt MJF wore, so I'm pretty sure if that held up, this would too. I also own the jacket, which was purchased off the rack by the way, it is not a custom piece. Also, I should tell you just because they aren't speaking up in this thread, I am certainly not the only person out there trying to uncover this info. The truly hardcore BTTF fans, the ones that probably have some of the most impressive collections, don't always want it known what they have, and they are searching EVERYWHERE not just ebay. The Class-5 vest was first found at a thrift store, for example, but regardless, even on ebay there is clothing from hundreds of years ago for sale, so while it might be incredibly rare at this point, if it truly was a mass manufactured item, someone, somewhere, must still have one.
The picture you posted from the Almanac is of the 2010 release, so again, with respect, until someone can turn up an exact original, this discussion certainly remains open.