Yeah, you could put it back in veg but I wouldn't. It will take at least 2 weeks to a month to reverse from flowering to full veg.
Flower it out, smoke what you get, then think real hard about what you want to do next.
a 10" pot will be fine the whole way, Right now you need to worry about it surviving the transplant.
More important than some "box" to grow in, is a reflector for your CFL's. Don't use tinfoil cause it absorbs too much light. What you want to do more than anything is focus the light you have into the small area the plant takes up.
Putting a small fan in the room would thicken up your stems in a week or 2. Just be sure the fan doesn't blow directly on your plant. Instead aim the wind at the nearest wall and let it bounce off and hit the plant.
P.S. 8"-10" now equals about 2' finished. If you veg it, by the time you put it back in flower it grow to 4'-6'.