VH registered unfortunately, as stupid as it may seem. RPL training in your case would have to be done under a part 141 training school approval, which means GA instructors with GA aircraft. Also I believe the endorsement has to be issued by a grade 2 instructor or higher, although I'm not 100% certain of that. Since it's an endorsement, not a rating, it doesn't require a flight test as such, you just have to demonstrate competence. I would suggest it might be a good time to chuck in a retractable and CSU endorsement as well.