Email Newsletter Template for MailChimp

I work for a company who are looking for an Email Newsletter Template for MailChimp. We already have parts of design but we're looking for someone to code the HTML. We're still working on the brief but what I do know so far is that we're looking the newsletter to be able to carry tweets, some sort of monthly calendar, and several small areas to link to our website content such as blogs, and employee profiles.

I am looking at a quick turnaround of about a week (I will provide a better brief once agreed), so ideal deadline is 17th July 2015. Please provide information on how long this would take and the cost as a result.