For option 1 I think you need a castsequence macro, bloodrage takes time to get your rage up (I think, I don't play warrior very much), so you'd end up with one button that you need to press twice (once for bloodrage and once for intercept once you have enough rage.

/castsequence reset=10 Bloodrage, Intercept

For the reset part I don't actually know what time would be best, but basically the number is seconds after last hitting the button before it will reset back to bloodrage, so in that macro if you use bloodrage and then don't press the button again for 10 secs it will reset to use bloodrage again. You can also reset on other conditions (like target changes), but I don't know which would be best for your needs.

You might also want to add in Intercept on it's own with a modifier key so that you can cast it without wasting bloodrage if you have the rage already. That would look something like the following macro, though I'm doing this off the top of my head, so apologies if I make any mistakes.

/cast [mod:shift] Intercept
/castsequence reset=10 Bloodrage, Intercept

Edit: The reason you didn't find a macro for this already is that it's probably more of a general warrior one, rather than specifically useful for multi-boxers. If you need a general class macro (rather than one you're trying to make work for a multi-box specific thing), then it might be worth checking the WoW class forums as well as they tend to have a macro thread.