Don't know "Britrock" as a genre/description but sounds like you're looking for Alternative Rock with its (post-)punk influences still intact.
If you don't get any suggestions you can check out the following genres on wikipedia and maybe you'll find something:
Alternative rock (the United Kingdom section)
Post-punk revival
Garage rock (mainly the "Revival" section)
EDIT:
Was listening to this earlier today, maybe this is the type of stuff you meant:
[youtube]30w8DyEJ__0[/youtube]