I need a website (high-load ready)

Hello guys, Let me introduce myself first. We are a group of Flash developers and we create various games in different categories. We have grown recently and now we are capable of converting our Flash games to HTML5 so we need to start one more game portal that would host games converted to HTML5. Our key requirements are: 1) High-load. We expect it to be ready for high-load. So we would like to know if you've made such projects before and you'll be preferred more if answer would be 'yes'. Experience in developing high-load websites is a Must! Please consider this before applying. By 'high-load' I mean have a website that is ready to serve 200-300K visitors daily. They will keep playing our games that are ranging in size of 30-70Megabytes each. 2) Ready to upgrade. It must also be made with an perspective sight on extending it so we that we could serve more visitors and it wouldn't require to change the codes, but just adding more hadware, servers or hosting plans. Features required: 1) Each user may register with us and get an account. It would also let him register using his existing credentials from G+ or Facebook (very generic and widely used feature) 2) Main page must have a bar on the top. And there will be 3 buttons: a) Main menu (list of game categories). That will be used for easy navigation purpose. b) Search (quick and easy way to search for some particular game by typing its name) c) Login button (described in #1) 3) Page layout should have two entites: our html5 games table and ad blocks as well. Layout must be designed for mobile devices, so it would show table of games in columns, splitted according to the available viewport width (2,3 or 4 columns) We also have an Ideal example of the website that we would want to have: gamesgames dot com (please respond in your message, that you've checked this website, so I know that you read my description completely) Please check it thoroughly and let us know if you made similar websites before and ready to help us. Estimated delivery time 30-45 days. Budget: $3-7K (highly depends on the actual feature list and will be negotiated in a more detailes way upon project agreement). My budget is limited but we are ready to negotiate it as we are focusing on quality first.