You can get ballpoint pens with USB storage from… anywhere. Amazon, AliExpress, Temu, eBay, etc.
Heck, if you place a bulk order for with a UK-based print-on-demand company they cost around 80p each and you can have your logo put on them. They're not unusual or uncommon or somehow exclusive to IW/TJC.
I will say - a reminder: I'm a technology journalist for a living - that flash memory inside cheap tech is never that good and won't last long. It'll either be slow, old flash storage no-one else wants, or they'll be using "binned" NAND that didn't pass the cut for other OEMs who have reputations. Don't go sticking any precious photos on them expecting to still access them in 12 months, nor plan to use them heavily as a) they'll have slow transfer rates and b) those will degrade much sooner (most novelty USB products are made with those tradeoffs in mind as the items aren't marketed/intended to be used as a proper form of data storage).