When I worked for PTE, we would occasionally get calls from people asking if they were still available. The last time I had the turbo room check was back in 2009. There were none and no plans to ever bring them back. Very few made it out the door when they were first relased. Then when they were banned from competition in TSE class, production of those 3-bolt turbine housings ceased. I think less than 10 were ever sold with the cantaloupe housing to be honest. Production switched and continued to thrive for the .96 A/R 4-bolt housing version of the PT88.
Those 3-bolt housings were specifically made for the old school, first generation PT88 turbo. The wheel specs were very proprietary and were never released publicly. I believe the A/R on the 3-bolt cantaloupe housing was .96 A/R if memory serves be correct. You might ask Neal Whyte from TX, as I believe he still runs a 3-bolt PT88 on his GN or at least he did. Those housings are rarer than hens teeth today.