£9 (plus £1.99 postage) is a good price for three pairs of boxers, I think. They are of the trunk style, and have some vivid colours and patterns on them. But for £3 per pair, I'll put up with that.
95% cotton and 5% elastane (the waistband) too, so will be comfortable.
Have a look for yourself, there are quite a few to choose from. A few of the styles come in different colours too.
Crosshatch Men’s 3 pack assorted colour boxer-shorts with assorted designs. All boxers have jacquard waistbands with contrast raised logo text & woven waist label. Packed in 3 pack box.
Fabric: Solid colour body: 95% cotton, 5% elastane