So...the one I have from the late 1700’s isn’t worth much, eh?
It would still be nice to have - and (speaking as an amateur in this area) it could still be worth hundreds or even thousands depending on its rarity and condition.
And Perot's 1297 copy (now owned by David Rubenstein who has loaned it to the US National Archives) is still a very valuable document - there are less than twenty known Magna Carta's from the thirteenth century and all could expect to sell for millions, if not tens of millions - but if one of the 1215s ever went up for sale, it would probably break all records for sale price for any document.