Hiya Hiya makes needles as small as US 00000000 (that's eight zeroes!). There are probably several online outlets that carry them, but I know you can get them from yarnmarket.com
Yup. They have them in both the 3mm (US 2.5) and 2.75mm (US 2) sizes. They're stainless steel circulars in just about any length you could ever want. I've got some (in much larger sizes) and love them.
On the stuffing leaking out, another tip I read somewhere (might've been here actually) was to use a pair of panty hose to line your toys with. Keeps the stuffing inside where it belongs. I should hasten to add that I've never actually done
this, so I can't testify to its efficacy. Also, I find that I tend to cram more stuffing into toys than they actually need. Avoiding this will also help keep the stuffing on the inside where it belongs.