The only time I saw girls belted at Secondary was when a group of 4 girls were called out to be belted for something by a male teacher. One girl had a bandage on one hand and could not offer crossed hands which was the norm – she got double strokes, 4 in total, on her one good hand whilst her friends only got 2 each on crossed hands.
When a belt was to be borrowed from another teacher, I seem to remember that it was generally a girl who was sent to get it.
I also remember one occasion at the end of term when the seniors had an auction of belts for charity. Two girls, one the daughter of a lady teacher in the school, were dispatched to borrow belts from teachers, including her mother, for the auction, after which the belts were returned to their owners.