I know all about cheap, I have kids... The Ferrari Gilda is the way
to go for a cheap hand corker that works; it only does real corks
though, it's not strong enough to compress a synthetic. I've seen
them for $18 to $25. The Portuguese floor model is around $40 -$60.

As to carboy sizes, the most commonly available are (In US gallons) 7,
6.5, 6, 5, 3 and 2.8 gallon stubby's if you can find them anymore.
Everyone that stocks suplies usually has the 6, 5 and 3. Gallon, 4
liter or 3 liter containers can be found for free from restaurants
that serve jug wines; they are usually more than happy to give them
away.

Joe