Are you in Whiteley Hampshire?
 I had some ally machined not too long ago by a company in Havant... I provided a 3D cad drawing which they just fed into their cnc machine and pressed go.
 4 fairly big brackets cost me £60. 
 Hugh Watson is the guys name: 
hughw@innovadesign.co.uk http://www.innovadesign.co.uk  If you need cad drawings done just give me some dimensions and I'll do it one evening.