Yes, you can use the sentence like that. If you want, you can use another expression in the second part of the sentence instead: even if someone killed me over it. even if it had/ got me killed. even if it means getting killed. But in this case, your sentence is also okay, because both parts are hypothetical, not real. However, your sentence in hindsight seems a bit unclear, so I'd use a workaround if I were you ;)

The answer is yes, you can use "would" twice. I agree with JulieD that your sentence doesn't make sense, though. It sounds like you are saying that you really want to get killed. It might be easier to understand with a different example: "I wouldn't sell my car even if it would make me rich." This means: "Selling my car would not actually make me rich, but EVEN IF selling my car would make me rich, I still would not sell it." Being rich is a good thing. It's something you want. But you don't want to sell your car. Therefore, you can say that you are not willing to sell your car, and you would not want to sell it under any circumstance, "even if" it would make you rich. In your sentence, you seem to be saying that getting killed is a good thing. You want to get killed. But you don't want to "do that." So you say, "I wouldn't do that even if I would get killed." It means, "I want to get killed, but I'm not wiling to do THAT, even if it would accomplish my goal of getting killed." In short, your use of "would" is correct, but your use of "even if" seems to be incorrect here.

Let's look a little deeper at your sentence. It doesn't make sense to use the negative "I wouldn't do that" because "I would get killed" . Imagine that the love of your life is trapped and you would do anything to save her. You would risk your life for her. So then you say "I would break down walls even if doing so would get me killed by the guards!" But if you did mean "I wouldn't do that" then you'd say "I wouldn't do that because it would kill me."