Just out of curiosity, which country are you in? It's difficult to make a recommendation otherwise.
If you live in the UK or Ireland, I would recommend getting the BBC HD Freesat box, which does not require any subscription and works with an existing Sky satellite dish and connects to the monitor by HDMI. This webpage gives a list of channels which Freesat carries, which includes the HD channels ITV HD and BBC HD. If you live in Ireland, I would recommend taking a trip to Northern Ireland to purchase one, as the Freesat HD boxes in Ireland are about twice the price.