Without even looking at your text it's obvious from the photos that it's a modern replica as there are the letters 'WRL' stamped onto Aethelred II's drapery. These letters stand for Westair Reproductions Limited.
Such English coins as well as Irish & Scandinavian imitative issues are found all over northern Europe and down through the Baltic region. As for why this replica was where it was? Very odd.
an example :
the first is a replica of a medieval coin struck in Milan , is was produced and distributed by an insurance company to all his clients , while the second is a genuine coin ... as you can see they looks very similar ...
Not with the early Vicky Bronze but with Edwardian bronze it is definately something to consider IMO.
Certainly including the 1944 second 4 over a tooth.
I don't think it was produced to be sell as genuine .... too different ...
moreover I think these copies were probably given as gadgets with some commercial products .... for example here in Italy a lot similar copies were given with chocolate , biscuits , newspapers etc during the 70/80's
I personally can't see a problem with laminating but I question why they are deteriorating. I have coin tickets (card discs) over 100 yrs old and apart from a bit of foxing they are fine. I would imagine coin authenticity certificates are modern (coins/tokens sold by SOME of the rip off organisations) which are worth diddly in the 1st instance. As Matteo95 suggests examples would assist with further advice.
Not discounting '9's, the above comments apply to all digits where variation has been noted.
From steamy Kyoto, where we have just walked miles to see red arsed monkeys being fed peanuts.
Jerru