Aquarium canister filter tubing..?

I read my canister filter has 3/4 thick tubing for the return and intake. I bought a filter off ebay and the tubing is VERY stiff and hard to place the intake on the tank properly cause the tubing wont flex. Where can I get different tubing cause this thick vinil tubes isnt working for me. Also the intake and return is rather flimsy. Can I swap them out with a intake and return from a different model canister as long as they are 3/4 size?