Depends on the type of rod you want to take.
a 4 piece travel fly rod will fit into a large holdall.
2 pice 10ft or longer will need a bigger case.
This could be what you are looking for.
Plano Airliner Telescoping Rod Case available from Amazon.com for $38
I`ve got the 4inch diameter Bazuka (6inch also available). Some people say they are a load of "whatever" but personally I cant see what the problem is. Mines been overseas on the plane 6 times in the last 3 years and going again this year, no problems with it to date and certainly looks after the rods.
Possibly not as shiny and nice looking as the Plano but not as dear either.
The Penn rod tubes come in a variety of shapes and sizes and are ok, i will be taking mine to Norway soon. The only other option would be to buy travel rods perhaps? allthough that would be expensive all your rods would be safely tucked up in your suitcase.