I'm puzzled - pyracantha flowers, usually produces berries and has ferocious thorns - there are not a lot of hedging shrubs better than that for security
My thoughts too Dove. Just stick another one in Nadger!
There's a list as long as your arm for roses. Classic roses has a very useful website that allows you to choose the qualities you want. Colour of hips, shape of flower, colour of flower....
Mahonia flowers at this time of year and is thorny - it may however be a bit too different in structure from your pyracantha hedge.