If you are looking for face masks, Home Bargains has quite a few.
Home Medics washable black 80% polyester 20% spandex face mask 1.99 each
https://www.homebargains.co.uk/products/18531-washable-spandex-face-mask.aspx
Shield UK washable face masks (3) 4.99
https://www.homebargains.co.uk/products/18587-shield-uk-3-reusable-washable-face-masks.aspx
Home Medics non-medical disposable face masks (50) 19.99
https://www.homebargains.co.uk/products/18588-50-disposable-face-masks-with-ear-loop.aspx
Home Medics disposable face masks (8) 3.49
https://www.homebargains.co.uk/products/18523-6-pack-disposable-face-masks-with-ear-loop.aspx
Nisbets Next Day Catering Equipment also carries face masks if you are looking for something to wear while working in a pub, restaurant or café once they open.
Ecotech EN14683 Type 1 disposable face masks (50) 44.99
https://www.nisbets.co.uk/ecotech-en14683-face-mask-type-1/ds148
Obrush ASTM Level 1 Type 1 disposable face masks (50) 44.99
https://www.nisbets.co.uk/general-face-masks-type-i/de780
Aumacom EN14684 disposable surgical face masks Type 2R (50) 64.99
https://www.nisbets.co.uk/surgical-face-masks-type-iir/ds149
Obrush EN149 Nor/FFP2 disposable respirator face masks (50) 199.50
https://www.nisbets.co.uk/respirator-face-masks-n95-ffp/de779
Word Up Design has a range of colourful face masks, if you’re more of an activist
https://www.wordupdesign.eu/product-page/facemasks