Shapeshifter rules for 3rd Edition are found in the Shadowrun Companion. About the only thing good you can say about them is that they don't get boned quite as badly as ghouls.
Fox shapeshifters have most of their bonuses to mental Attributes. They make great mages, but would be middling, at best, in more physical roles. A fox shapeshifter sniper isn't really making the best use of a shapeshifter's advantages.
SURGE is found in Year of the Comet. I don't have that book, so I don't know how it compares to the SR4 version. But while you can make a furry character, I am pretty sure that character would be furry all of the time, rather than having a furry form to shift to.
You might be best off playing a shaman with a fox totem and the shapechange spell - he could use spells such as manabolt instead of a rifle. Just a thought.