In reply to gammarus:
A pal gifted me a pair of 174cm skis a couple of years back, on the condition that I arrange carriage. I used ParcelForce: they e-mailed me PDF postage label that I forwarded to my pal to put on the package. They picked it up from his address and delivered it to me four days later.
Cost £35 which sounds pricey but it got the job done seamlessly so no real complaints.