How old are these pics? Those are definitely Cdn made "Grizzlies"/M4A1 Shermans. You can see the unique Cdn pattern tracks and sprockets. The RCAC Museum in Borden had a Grizzly Firefly conversion on display many moons ago. if those tanks still exist in Portugal they would be a very rare beast.
http://web.inter.nl.net/users/spoelstra/g104/p.htm