It’s definitely not from the Revolutionary War. The styling of our Royal coat of arms has undergone several changes over the years. What can be said for certain is the arrangement of three English lions in the first and fourth quarters, the Scottish lion in the second quarter and the Welsh harp in the third quarter cannot be earlier than 1801.
There’s not enough of it left to put a firm date to it but, from 1801-1837, the Royal arms also included an ‘inescutcheon’ (a coat of arms within a coat of arms) for the House of Hanover… like this:
The inescutcheon was removed when Victoria came to the throne in 1837 since, as a woman, she was not entitled to those privileges as Head of State. Semi-Salic law prevented females from inheriting the Hanoverian throne while a dynastic male was still alive and so the title (together with the use of the armorial) passed to her uncle, Ernest Augustus. Whatever the badge might be, I would suggest it’s Victorian or later.
Yes that’s the general Royal arms emblem Don, but the problem is that it saw wide usage over a long period, for general service cap badges and other purposes.
It’s the details that are important. For the picture you posted, the arrangements of the charges in the quarters again say that one can’t be before 1801 and the absence of the Hanoverian inescutcheon puts it after 1837. Then, in addition, you can narrow the date down further from the style of the crown surmounting the armorial. It’s what we call the “Edwardian” crown which was the choice for Queen Elizabeth II, so for the example you’re showing, that puts it 1953 or later. You can use these crown styles as a general guide to dating many British official insignia:
With so much of the OP’s item missing, it’s not possible to be more specific about the date or purpose, other than “Victorian or later”.
least that one looks like pewter... however the difference there is mine doesn't have a pin but a bent over piece of brass like attachment and mine has separations between the top and the crown that is missing
Matt-Klein, I don't think it's going to be possible to reliably identify or date. There's too much of it missing. Maybe you don't realise just how many purposes there were for our Royal coat of arms (official and otherwise) in various badge-like forms. My opinion stands that it's not earlier than Victorian, based on the style of the arms (and can't possibly be earlier than 1801 because that particular armorial didn't exist prior to that date).
The only other thing I would offer is that the workmanship of the representation looks to be of poor quality execution. The engraving of the mould or stamp from which it was produced is crude. That in itself doesn't mean it wasn't produced for some official use, but it does rather point against it.