Can't help you on a local supplier as i'm not local
but that price seems high, the part is circa £30 so thats £100 to fit it, and it's an hrs labour at the most for a competent mechanic.
If I were you I would seriously consider giving it a go, i'm not mechanically minded and I did mine in under an hr following the various guides and that's on an AXX with the banjo clip that is supposed to be a bit harder.
Failing that, maybe a forum member in your area might be happy to help you do it and then you'll be comfortable doing it the next time as most people are making this a part of their standard serviceable parts now.. Save you some dollar in the long run