Both Aldi and Lidl do biking stuff quite regularly and in larger stores all the time. Prices are super cheap and quality is so so as you'd expect. Similar to Decathlon basic range stuff. I have quite a few bits and pieces that haven't fallen apart immediately such as winter mountain biking tights (less than £10 I think, had them for about 5 years and still fine), and a great biking pack with bitey tube/bladder thingy (£7the lot, bargain).