Searching an Icon Designer for long-term business

Hello everyone,
I am searching an Icon Designer to deliver packages (collections) of icons based on different themes, like for example medicine, business, sports and so on. We would work together hand in hand, as I would give you the themes and you would deliver me a collection per week.

The icons should be black on transparent background, something like this:

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My payment would be dependent on the amount of icons.
For example 0.5-0.6 $ / icon. So if you would deliver 5 sets of 50 icons per month, it would be 150$ each month!

The icons should be unique and individual. I would love to hire you for at least one year!
Please provide your knowledge in designing and your portfolio.

Thanks and many greetings