That makes things a lot easier! Getting a flex is a hassle in Melbourne at least as only 2 artists will do it. But you have a lot more luck with capsules as they are practically piercings.
I can’t find specific body mod artists in Adelaide that mention it but my best suggestion is to ask non-Franchised piercing and body art shop. Thats how I found my favourite body mod artist actually.
Did some looking:
http://www.venomart.com.au/ {Says they don’t mind unusual piercings}
http://piercingperfection.com.au/ {has a very big menu including dermal piercings so most likely wont be scared away by the NeXT}
Let me know if you need any more help