The first question I've been able to help answer - yay!
We used a water bottle cage intended for a bike. It fits a 600ml Caldex Classic Bunny bottle perfectly. Like this one:
http://www.jejamescycles.co.uk/tortec-bottle-cage-alu-silver-id52188.html
D x
ETA I guess if you have more than two bunnies, you might need a couple, as it doesn't fit the 1.1l bottle.