Fuel filler cap

I'm looking for a lockable fuel cap for my 84' defender.

I saw one on eBay that said it was for 1983 - 1994ish which I assumed would be suitable. However having double checked on Paddocks it says that one is for 1984 vin no's AA259678 onwards and mine starts AA22....

Would I be right to assume this won't fit... And of not any ideas of where else to look? Any help much appreciated.

Cheers

Pretty sure you cant get them..i've never found one...you can put a bodged latch and padlock arrangement on.

That may be the only option then... Will have to take a look at it...