Non Pork Bacon Alternatives
The problem is, few animals have anywhere near the fat content of pork. Bacon is actually leaner than some other cuts from the pig (Mmmmmm, fatback...Had fried fatback once, true story.)

So to get a cut of meat with as much fat as bacon? Pretty much impossible. But bacon is also about smoky flavor, and delicious nitrates (and gas phase polycyclic aromatics, the best carcinogen on the planet). There is duck bacon, lamb bacon, beef bacon. There's probably veal bacon, but that'd be pretty expensive.

Most people recommend lamb bacon, if you can't handle pork, but the beef bacon is probably easier to find in the US.

Edit:

Behold fried fatback!