How to integrate subscribestar tiers for restricted content

Hi,

I want to set up a subscribestar support account with 6 tiers of access to content depending on the tier.

My idea is just to give a simple code for each subscriber tier to unlock the content for that tier. I’m not too concerned about making it super secure. If a subscriber publicizes their code on facebook or whatever (unlikely I think) it would not be the end of the world.

How can I do this? I tried using the “simple membership” plug in but it can’t work in that way. Is there a plug in I could adapt for this?

Many thanks in advance for your kind advice.