Can we have "Issue only" users not counting towards seats taken

In a organization with paid seats we have a private repository setup for a customer. We are 4 - 5 ppl working on issues, developing commiting etc…

Customer has 50 users. They only need to report issues, comment and see status.

I dont want to pay for 50 very occational users for them to create a few issues. The only meaningful way I’ve found is to create a totally different organization, free, add a private repo. But then its totally disconnected.

How would you do?