Playadito is one of the cheapest and most common ones. There are premium, organic, smoked you name it.
And don't worry about filling it up because it's not normally the case with large mates like that one.  Just keep enough in it to cover the low part of the straw and about 1/3rd of the mate and not make a soup out of it. The yerba will gain size as you pour water.

Be aware of a common story shared among old folks here: no one likes mate at first. But gradually and then suddenly:
https://image.nostr.build/6620e97e715c72e8e34c7ac1f7c2ae122519413990fced554d3f863e8fbc5496.jpg

You will find yourself walking the streets like this.
 

 🇦🇷🧉🫶🏼 mate lovers