You are asking three questions here, (1) were to get investors, and (2) should sell your company (3) for how much should you sell. To answer the first question, go to www.breadstreet.com ,the second, I am not qualified to answer, and the last is to get a business evaluation to find out what the company is worth. The people at Breadstreet.com are very friendly and can help you out with your other questions.
I would suggest going to www.breadstreet.com to go find angel investors.With the backers your talking about I am sure that you will have little to no problems getting the investors you need for your project.
I would suggest to get angel investors.With start up and early stage businesses for the most part they get the funding through angel investors.One the best places on the web that I found to help is www.breadstreet.com .