Spain, 5 pesetas 1871?

Can anyone give more explanation about this coin?
I do not have it with me for the moment and it is behind plastic.
But the 'crowned PG' above the date puzzles me
The other side is the normal '5 pesetas' KM 666
Is it to mark the country 'Azores'?
https://en.numista.com/catalogue/pieces27874.html
Thanks

Yes, this coins is for circulation in the Azores, but they are commonly faked...I have one of the fakes.
There should be marks on the reverse to correspond with the countermark.

Here you have a good thread about this countermark and its fakes
http://www.worldofcoins.eu/forum/index.php/topic,5727.0.html

I think the design of the crown isn't the real, and the wear of the countermark is less than the wear of the coin. Check also the stroke in the reverse.

Thanks for all the info!
The counterstamp indeed looks very modern