The only near-substitutes I've found are sugarfree Tang or Keto brand Ket-oj. Orange juice is WAY up at the top of the glycemic index, in fact we're trained to give oj to diabetics to bring their blood sugar up as fast as possible when they've had too much insulin... I don't know of any low carb plan that lets you have it.

The good news is that it's possible to "re-train" your body and you won't miss it so much forever!

Some good snacks I've found are beef jerky (read the label, though, as some are loaded with suger!) string cheese, pumpkin seeds, sunflower seeds, and a limited number per week of low-carb bars such as Advantage or Keto.