Rare 'Anglo-Saxon Helmet' on Sale in US

Anglo-Saxon helmets are not what one would call a 'common' metal detecting find. But here's what purports to be one:  Ancient Anglo-Saxon Iron HelmetLot 51 sold by Artemis Galleries

Anglo-Saxon England, ca. 6th to 8th century CE. An exceedingly fine iron helmet comprised of two wide iron bands attached with rivets supporting an iron "crown." [...] Size: 8" L x 7.6" W x 6" H (20.3 cm x 19.3 cm x 15.2 cm) [...] The Saxons were fierce bearded warriors who fought with a ruthless, surprise attack style that intimidated many, even the Romans. Anglo-Saxon society revolved around warfare. [...] The need to obtain more land for distribution encouraged policies of conquest, and the kings of Wessex were particularly successful because they were able to expand into Cornish territory. Provenance: Ex-private United Kingdom collection, acquired in the early 1980's. All items legal to buy/sell under U.S. Statute covering cultural patrimony Code 2600, CHAPTER 14, and are guaranteed to be as described or your money back. A Certificate of Authenticity will accompany all winning bids. [...] Condition Intact save one small area, near choice.

There's that "All items legal to buy/sell under U.S. Statute covering cultural patrimony Code 2600, CHAPTER 14" excuse again. So that means that the collector who obtained it obtained a UK export licence for it then? Can we see it? Can we see inside the helmet, is there any trace of a lining or the attachment of additional metal or organic elements? What does the other side of the riveting look like? What about the edges of the sheet elements making it up, why are they so rough and not cut straight if they were fresh metal when the object was assembled? Can we also see a helmet 20x 19cm displayed actually on Bab Dadge's actual dolichocephalic head - that is a rather strange hat measurement - especially if the thing had a leather lining. The description is hardly very precise.

I'd also like to ask the proprietor of this antiquities shop which Romans did the Anglo-Saxons fight in Cornwall in the eighth century? Instead of an extensive crap narrativisation from the Ladybird Book of British History, why do we not get a professional description of the object itself, its actual technology of manufacture, current state and collecting history? Like, was it shown to a museum in Britain when it was found?

There are only five other AS helmets known - why is this a sixth if the typology is completely different from the others? Or is it too cynical to ask whether "United Kingdom" is used here to launder a find made somewhere else, because walking off with archaeological objects found while metal detecting is legal there and illegal just about everywhere else? Will the British authorities intervene in this auction, or will they just judge this item to be a crude pastiche or fake (for example created by assembling elements cut from excavated WW2 helmets with false rivets) and not bother?

But this is the  second one (at least) that Mr Dadge has sold recently to some collector or other.... with the same spiel and the same method of being put together. Odd, that. But hey, "antiquitity dealer" eh?