Camperize are still listed is some web business listings, but don't appear in the latest Business and Govt phone book.
http://www.tuugo.biz/Companies/camperize-industries/0050003351882
Trakka used to make pop-roof conversions of the T3, but I don't know if they would still have their own moulds.
http://www.trakka.com.au/index.php
Discoverer Campers (who evolved from John Terry the Kombi King at Homebush) were located at Milperra in the late 1990s and early 2000s. They were taken over by Tysons Pty Ltd and moved to the former Fenner factory on the corner of Milperra Rd and Edgar St Revesby in 2004. They had quite a collection of fibreglass pop roof moulds, including VW T2 (Sopru copy) and T3, as well as Holden Shuttle, Mitsubishi L300, Hiace anbd Nissan Urvan. They were all thrown out when Tysons went out of business in 2006.