Chuds, I have to agree with Frank and Speed. With the market like it is, you won't find a qualified person who is willing to pay for a horse like that. Unfortunately, it is unlikely that you will be able to find her a qualified home even if you are giving her away for free. With costs the way they are right now for hay and gas, very few people capable of handling a horse with "issues" want one that is that age and has that many issues.
Not to sound harsh, but I believe the only people that will end up interested in this horse will be the inexperienced bleeding hearts, the people who choose the old, sick crippled horse out of the kill pen instead of the young, saddle broke one, because they feel sorry for it.
With her age being what it is and if her issues are as bad as you claim, the kindest thing may be to spoil her for a few days and then have her euthed. That way, you can know for a fact that she will not end up in some horrible situation further down the line.