Build an Online Store

I am solo ad seller. I basicly have big email list, and I advertise to that list, and sell that advertising. Now, I can only deliver for example 200 clicks daily from that email list.. But, when people order, they can choose packages of 100, 200 or 300 clicks. So, now I need calendar implimented in my shop. And in that calendar I can set how many clicks I can deliver daily. So if I set that I can deliver 200 clicks daily, and someone orders 100, then for that day, there should only be 100 clicks left available. And if someone orders other 100 clicks, then that day should turn red on calendar, and be disabled. But, if someone orders 300 clicks, and I only have 200 clicks available, it should take 100 clicks from next day. If someone actually understands what I mean, please give me a price, and ask any questions you may need. I'll show you my website and explain in better detail what I need. I also added an image to show how calendar should look like.