you could easily bend (by hand) the thin copper pipe that would be best for this.
i think its annealed that is "soft copper" pipe or un-annealed. either way its very easy to bend.
an old homebrew trick to stop the pipe flattening is to fill the pipe full of sugar or salt, it will then bend well in your hands without kinking etc.
best way is start with straight pipe tape up one end and fill with fine salt
then tap tap it on the floor vertically then fill some more and repeat to make sure its full.
to get the salt out just put it in a pot of water and boil, the salt "melts"
if your going to heat the pipe while bending use salt..... i know that from experience...
forgot to ad, your local ENZED is a great source of pipes and fittings and they deal with lots of interesting machines they know how to look outside the square :)