Why does everyone always want instant results??
Holly will take several years.
Beech grows quite quickly and, altho not evergreen, the brown leaves stay on throughout the winter until the new growth begins in spring. I had a very thick one on clay in a previous garden.
What about a mixed native hedge? There is an offer somewhere in this month's GW for whips (barerooted) for less than 40 quid for 5 metres.
Other possibles are berberis (but beware if you have little kids) and various rosas (again barerooted would be by far the cheapest)