I've been using solidworks' sheet metal for a while, but it's the first time I'm challanging

to create a part.

I've been working for several hours to imagin how to make a part as the following image

I'm sure there's more than a hundred way to do it, but it seems that

I can't do it without somebody's help.

this image is a section of a part in a 2D cad.

I'm using Solidworks 2011 SP1.

Any kind of help is much appreciated.