Lisa and her mother found her suit at SaveMart, a huge discount store in Wanganui. There's a SaveMart Recycled Clothing Centre in every main city in New Zealand. I've encountered Frederick A before, a garment memorable enough for me to recognize the label when Lisa's mother mentioned it, so there's a chance that you could find something similarly delicious. SaveMart turnover includes thousands of garments per day, so if you had a look last month, it's worth having another look this month.
All the best, and let us know if you find something you love!