Keystone and a few others made those.. They dont make them anymore ..
Possibly someone does. I dont have time to look now..
They make a two bunk one..
http://www.keystonerv.com/outback/#/floorplansYou can get the front toy hauler and put quad bunks in front???
http://www.keystonerv.com/outback/#/floorplansBut the one you like was made 2009 last year I believe. Thats like 28 feet. You may as well get a regular newer quad bunk if your going that length..
KZ spree 289ks
Video
https://www.youtube.com/watch?v=J8VwxrwMxSY