I think it can be easily done even using HTML, but if You want I can make some PHP page with the data stored in an SQL database.
EDIT: I did read Your PMs, I just for some reason cannot reply using the freelancer.com PM system.
I can start from Monday around 8 AM GMT time and to replicate just the diagnosis tool (meaning the questions with different branching choices and the final recommendation), it would take 1 or 2 days.
I would just like to ask if it should be just a hardcoded PHP or I can use a MySQL database + PHP (question system)?
The second option would be more sophisticated and easier to modify in the future (adding new questions and answers), but requires access to a MySQL database.
EDIT2: Yes I see your messages, I just have trouble writing them directly to You. I did some research regarding that problem and Freelancer.com does it intentionally, so employers don't get spammed, by the bidders.