I doubt they would be salvagable. The main issue I think is timing. As @chester said, unless someone is in a hospital or even an accident where the organs can be removed rapidly, I think there is a fairly narrow window in which they can be saved. Obviously, you're not going to highlight to medical personel that you have just commited suicide. They may get there in time to save the person and- that will be their priority I imagine.
Also, I'm not sure the degree SN messes up the major organs. Plus- the body will go for autopsy I imagine in the case of a suspicious death. All unnatural deaths are probably investigated I would think.
It's yet another reason why assisted suicide should be legalised. Those who wish to could help others to live via donating their organs.