As I said to another member in another thread you will need to take what you do know and expand it to suit the larger project.
For example, if you know it takes you x number of hours to code a couple of pages, then multiply that into your required number of pages. Do a couple of catalogue items and time them, then multiply that by 230 x hourly rate.
Basically work on what you do know and expand it to what you estimate it should take. Make sure you are conservative, because you don't want to underquote. You also don't want to overquote, but at least with overquoting you can give clients a refund.
For a project as large as this, I would really consider doing it only on an hourly rate basis, as quoting can go horribly wrong and you can be tied into a monster of a project.
Good luck Steve