I found the watch bands and coupon below when I was searching for a replacement.
Ac Union branded items, from 3rd party seller TwinkleStore, has a 50% off coupon for watch bands on Amazon. The coupon is on the product page, you must click to use (discount shown at checkout). Seems to be a one time use coupon, only valid on one item. The expiration timeframe is not known. Multiple Amazon accounts are needed to use the coupon additional times.
Free Super Saver Shipping or Free Shipping with Amazon Prime.
I have no idea about the quality of the bands, but for $4 or $5 bucks I'll take the gamble.
Colors range from black, brown to blue. Sizes are 18mm to 22mm.
20mm Black w/ traditional clasp at $3.99 with coupon:
20mm Black w/ Butterfly Clasp at $5.99 with coupon:
20mm Black w/ Butterfly Clasp fakespot rating is a "D"
Other watch bands are as bad as an "F"
Overall seller rating is a "C"