Hajo, finding a picture of that size is next to impossible on the net. Some pics are as large as 1024 but the majority of those have been expanded to that size, with grain, fuzzyness etc. The norm is 800 maximum. With even that, the times that the ratio is correct for a desktop is very rare.
I have a 1024 desktop. What I did so I can have them all as desktops as the mood strikes it make the "maximum" width 800 pixels using a black desktop background. The pics then don't hide behind my one row of icons and I can use any pic regardless of "ratio".
I do scan calenders ( DONT TELL ANYONE ) and with those the size you request are doable. Straight scans ( takes four ) yield a size of 3500 pixels or better that I merge, clean up and scale down.
Just about every pic at the website has been fiddled with one way or another. Whether changing contrast, saturation, removing imperfections, or removing backgrounds or adding them.
This F4 shot had great lighting, brought out the colors of the plane beautifully. Problem was it was a grey overcast day with a bunch of airport buildings in the background. It wasn't cropped well with a whole bunch of runway at the bottom of the picture. Found a simple solution from another photo that I had. Combining the two made for a good F4 photo instead of a blah one. The plane just jumps out at ya.
Hajo, take a look through my 47 shots, email me your choices. I'll get back to you on whether the shot you like is doable.