You might try playing with variants, although I don't think that is exactly what you are looking for.

One way would be to hide the price, and in the description, have a link to your quote page. I use a module called helferlein forms, which allows me to make custom forms that a user would fill out. I have used it for a number of things, including requesting quotes, registering for events, and so forth.

So, back to the original question; you could "Hide the price", and have a link in the details section to request a quote, that would take you to your quote request page.

I ended up not using the cart for things that needed to be quoted. Instead, I have a page that has a "Request a quote" link, and I used helferlein form to allow people to fill out a quote request. That form then gets saved in the database, as well as emailed to the appropriate salesperson for follow up.

If you'd like to see it in action, drop me an email greg@advantageemblem.com ... my site is still under development, but I can let you see that part of it.