I live in Australia and I got a 3DS XL not too long ago, and needed a case for it. This is where my journey began... after weeks of trying many stores only to find Mario or Pink 3DS only cases, but I wanted a generic one even looked at pencil cases/PS Vita cases but still no luck.... I had lost hope. So today I went out looking again wishful thinking I guess AND THEN I found it a gem of a case and it was in a clearance box in JBHIFI. It cost me $15 well worth it. It holds 12 cartridges, the 3DS XL is really easy to get out when on the go and very good build quality. It is made by PowerA I recommend the brand after doing some research to others.
Here is what it looks like: i.imgur.com/pumukfm.jpg