Acer palmatum fits this description. There are many forms of it too.

More specifically, you're describing Acer palmatum 'dissectum' varieties, although Acer palmatum 'Crimson Queen' would fit that description too, but has dark leaves.

Acer Palmatum "dissectom is the one." 'Red Dragon' is just as you want and a better colour than Crimson Queen. A really glorious red when the sunlight catches it. They do need shade and do not like to be waterlogged. Mine died last year because the soil retained all the rain we had and the roots rotted. It had lasted 10 years in the wrong place. I was devastaded as it was sooo beautiful. Good luck and have fun searching.

thanks very much songthrush, i shall scour the garden centres at the weekend, wish me luck!

Andyf of course I wish you luck. You may find a specialist acer grower near you on the internet. Have a great weekend.