Good supplier of iPhone 6s plus batteries (UK)?

Hello,

Just wondering if anyone knows of a good supplier of iPhone 6s plus batteries? I got an iPhone 6s plus that needs a battery replacement as the original drains a lot faster now even on standby.

I saw that iFixit stock a battery for this phone and I was about to buy it. However, the high £12 postage cost put me off. It brought the cost up to around £35. I ended up looking elsewhere and took a gamble on Amazon. It costed £18. Unfortunately, it did not pay off as the phone regularly reboots and doesn't properly charge.

I put the original battery back in just to make sure no damage occurred to the phone during disassembly/reassembly. That one behaves fine with no reboots and charges all the way to 100%. So it's clear the battery I bought is bad.

I'm hoping that someone knows of a good supplier that ships to the UK so I don't have to order multiple batteries from multiple places hoping they work.

Appreciate any help.