brittle vacuum lines

i just replaced mine with the small plastic vacuum tubing from autozone. not sure what size...small...i think they only have one size there. i used heat shrink to ensure that the seal was air tight.
 
You can get new bulk plastic hard line but I generally won't use it either. I do like the guys do, and use rubber line as a splice or even as a new replacement run. Either way works.

Good luck.