Well this has to be a world-first!
Over the years I've bought loads of 32650 LiFePO4 cells with varying degrees of success!
Our garden floodlights are powered by "Franken-Packs" made up of matched sets of the rather less good cells (some are absolute junk). Space in this case is not a constraint.
I have an application where space is a constraint, i.e. an upgrade to grand-daughter's e-scooter which currently has knackered sealed lead-acid batteries.
Luckily, I hit paydirt with this seller. I think they are a reincarnation of a seller I had good results from in the past who then had a load of iffy cells and vanished.
Anyway, these Tipsun "6,000-6,500mAh" cells actually test at >6,000mAh.
Get 'em whilst they're hot!
https://www.lazada.co.th/products/i1927620957-s6091720828.html
EDIT Before anyone asks, no I'm not affiliated in any way shape or form with this seller