I couldn't find those speakers at the UK version of the Newegg site (your link doesn't work for me), so I chose a random pair listed at £43.54 and added it to the basket. With estimated VAT of £8.71 and shipping of £32.30, the total came to £84.55. So almost twice the stated price.Newegg does ship to the UK specifically though. So it would be worth putting them in his cart, going to checkout and see what the cost comes out to be. If you do that OP, let me know what it says.
A more expensive pair at £82.12 had VAT of £16.42 and shipping of £48.07. And a pair at £161.99 added VAT of £32.40 and shipping of £42.94.
So the shipping drops as a proportion when the price rises, but it's steep compared to domestic shipping (especially as you can often get free shipping here). Considering you'd forfeit any protection under UK consumer rights laws, and you'd almost certainly have problems with warranties, returns, or any kind of customer service if needed, I really don't see any sense in buying from the US.