Also just a heads up, I work with advertising companies in my day job and even at top end click pass through rate we pay $12 per 1,000 ads clicked. So 350 to 500 visitors/month should cost in ad advertisement roughly $5-$6. You need to be passing through like 100k + a month to get any decent revenue from visitor counts. I know there are some companies that will pay more for a limited time, such as Call Of Duty titles pay roughly $20 per 1,000 ads clicked but even at that it's nowhere near the same number.
That being said I don't know you or your streams or social media, just saying in terms of what online advertising usually costs.