Were I DM, I'd rule "no". Too much cheese factor. If nothing else I'd invoke the "3.5 rule"... Pre-3.5e non-updated stuff (before Dragon #309) isn't designed to be meshed with 3.5e stuff... at least in my book.
I don't think I'd permit ability score bonuses of the same type to stack (double/triple/etc.) in any case, except for Power Attack/FB ability... explicitly stated in the rules.
BTW, does Dead Eye shot have the same constraints of Vital Aim (Str 10+, not effective vs. targets immune to sneak attacks...) ??