As far as I can see it is bottled in the UK . The price doesn't make a lot of sense , unless they are just trying to steal sales from the competitors.Thats a very good price.
It may be imported in bulk and bottled locally - that's the only way it could get close to that price.
If it was imported from London directly , it should be around 450 pesos.
Local bottling shouldn't affect the quality at all . I would imagine that Diageo the brand owners will carefully control wht happens overseas.