Do You know this body? Not?
In fact, it’s a 400d body, equipped with a 350d shutter. It’s the same, in which I’ve found the free screws. I was not sure, if the problem was only the shutter (which has only 15-25000 exposures), or something else, so instead of buying a new shutter, I’ve transformed one from a disassembled 350d.
Visually the only difference is the flex cable. After mounting the whole thing together, it started to work.
But do it only on Your own risk.