Hard to get from a store? Hard to get if ordered on line? If you can order on line and get them shipped to you (may not be possible, I don't know) then either CZ USA or CZ Custom usually has, in stock, about every spare part you may ever need.
Cajun Gun Works and CZ Custom also stock/sell a lot of aftermarket parts as well.
If they can ship the parts to Argentina then check them out on the internet.
Oh, so far I've not broken anything on my P07 or P09 but I've bought springs, pins, etc., just in case.
An old guy that used to work with my dad said, "Better to have it and not need it, than to need it and not have it." I think he was talking about keeping old stuff around for back up or spare parts, but it still works out with new stuff, too.