I know someone who sells hockey gear including gloves, tracksuits and shirts, and he buys them from factories in Pakistan. I suspect they provide a range of designs and materials to choose from, and he specifies the colours, and designs any emblems such as team logos. I can’t really ask him who he buys from for obvious reasons.
The alternative is to buy a big name brand and deal with the U.K. or European distributors, but of course that would cost more, but require less work and risk.