A pair of my Linda Chow uniform pants lost their clasp too. I just got back - had a short lay over in Hong Kong. Linda Chow (the other girl that worked at her place, actually) took my pants in the morning, and had them delivered to the hotel that same early evening with a brand new clasp. No charge.
Shirts: Pilot House (
Pilot House, Pilotshirts.com for pilot shirts, airline uniform shirts and accessories) are awesome.