It looks like Prima Luna likes to private-label some of their components: Duroch caps, Prima Luna-branded tubes, etc.
As has been pointed out already, those caps are probably just rebranded by a legit manufacturer, in the same way the generic-brand cat food at the supermarket is made by the same agro conglomerate that makes national brands. If there is evidence regarding the quality of those caps that makes their immediate replacement a must, it hasn’t been shared in this thread.
Also, in typical audiophile fashion, capacitors are the object of endless hand-wringing while the mediocre, entry-level Alps volume control goes completely, totally and utterly unnoticed. If anything in that unit needs replaced immediately, the volume control is it.
I read the page you linked. Kudos to Prima Luna for delving into and showing high-res pics of the circuitry, but the puffery is so brazen that they actually hype their budget pots! 😂😂🤣
Alps has made great pots, but the Blue Velvet ($15 sans motor) isn’t one of them. Prima Luna are correct in pointing out that the Blue Velvet beats a crappy encoder and a $2 digital chip, but that’s faint praise.