I’ve purchased good stock online from joshs frogs and saurian plus local expos. My experience with Patrick at saurian was excellent. Ferns frogs is near where I live and she has exquisite stock but she doesn’t ship she only does expos in New York. You could also try Frogs n things. I dont know where you are located but bear in mind if you are having frogs shipped you want someone with good follow through and any of the aforementioned sources would suit you well. Also any of these vendors at an expo would be recommended if you don’t want to deal with shipping.

As as far as pumilios go, as long as you are getting cbb stock it’s doable for a beginner but there are a few things to keep in mind. They can be very territorial so you need a large vivarium if housing more than one and generally only sexed pairs are preferred. They are also small and some will only feed on melanogastor or springtails. Rather than get into all the specifics I’d recommend you read “The Complete Oophaga Pumilio” by Frank Steinmann. (The English version is available on Amazon. It was originally published in German). This book essentially answers all questions regarding pumilio.