Alter image to fade left & right edges to a single color

Hi, I need the attached image edited to fade the left and right edges into a consistent dark blue color (use the darkest part of the existing image as a reference - the bottom right hand corner), to allow me to seemelessly embed the image into a website banner. The image is to be widened as needed to perform the blending (i.e., it should not be cropped or any part of the existing image altered). I also want a 'filler' image (slice, whatever it is called), which is the same color as the newly colored left & right edges of the main image and is 20 pixels wide and at least the same height as the main image. This will be used to pad out the space either side of the main image on the banner (repeating over and over, depending on the width of the screen of the person looking at the page). I need this ASAP, so if you can't do it immediately, please dont bid. Please contact me with any questions. thanks.