You don't need to buy the entire line. Any automotive a/c shop or hydraulic hose shop can replace the rubber hose MUCH cheaper than buying a new line.

As far as seals, it will have o-rings or it will be a flare connection which will require no seal to be replaced. It is probably an 0-ring and is a standard item from the auto a/c shop, or from somewhere like www.ackits.com.

Hope this helps,