Matt
For Subic wrecks and PI Caves you could PM Bruce Konefe (ANDIBK). He is very familiar with the area, lived there and also does cave expeditions. He checks Rebreather World daily.
There is a Subic dive shop and the owners name Johan. They are setup for technical diving.
Johan's Beach Resort - Subic Bay, Philippines
Also see this thread on a Coron trip. The operator may be able to help you also.
http://www.rebreatherworld.com/rebre...er-2008-a.html
Hope that helps. I will be in Thailand and PI also in Sept-Nov so I will be interested to hear your advise.
John