"Buy" yourself the Adv Rec Tx certificate. Most will do it OC but IANTD allows you to take the course on rebreather as well. The buy here is in quotes since it's basically Adv EANx but with a bit of explaining about effects of Helium and the same drills that you should be intrinsically familiar with....
After that you have that card to have your tanks filled with and the other to dive. That's at least what I did. Now my LDS does nothing wrong and he "doesn't know" what I use it for. Well maybe he does, I've demonstrated the unit on several occasions during club events
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This is basically how it works for me with my IANTD training. I am still in the training part of it and don't have a helium card yet though. My LDS is also my training facility and I have no problem getting fills locally.