Or you can try to find a store near you (here on the Durable site), that sells the Durable Coral mini box, which includes a free pattern.
Catona (25g) and Catania(50gr) are good alternatives. But actually you can use any kind of yarn with matching hook size, you like.
Some of you who already bought the box or the pattern asked me to explain the joining a bit better. So I made a photo tutorial and a video. Hope this will help.
Like the pattern says, you finish 1 motif completely and next motifs you will join in the 9th row as you go. In the 1ch-sp you wil use the 1ch to join and in the 5ch-sp you will use the 3rd ch to join. Note that you are not joining in 3ch-sp!
Hope this makes it all clear now!
I also made a video, without sound though cause my voice sounds horrible at the moment.