I can recommend Halfords Green Stuff tyre service, I have not had a single puncture in 2 years on my 1000 W powerful bike, I found them as cheap if not cheaper than Amazon for most things, they are really trying
Unfortunately, this deal is no longer available
Join British Cycling for 10% cycling products all year round at Halford, there’s other discounts and benefits like liability insurance and legal aid (hoping I never need it)