I just thought it worth mentioning that Screwfix now do free delivery to Hungary on orders over £100. This could be useful if you need things not available in Hungary, like push fit plastic or compression brass pipe fittings. They don't offer the full range of goods, just the smaller items. The other advantage is having instructions in English!

While not strictly the same thing, there's a UK website TheHut.com (a kind of mini-Amazon, mostly entertainment/clothes) which does free European delivery on all orders. Some people might know it better as Zavvi, as it operates under both names, but I think the offer is only available through the former.

I mostly use it as I'm a bit of a gamer, and games here in Hungary often come at a small premium or less popular games/limited editions often aren't available.

Thanks Fib, worth noting