I think I know what you mean now, the hard line that runs from the junction block in the wheel arch to the abs pump ?
So you have the rubber hose from caliper to junction block , then the hard line from the junction block that then run to the abs pump
If thats the case a replacement would be available from any Seats dealer (have a look on here) or failing that I am pretty sure you can get repair kits where you cut of the damaged bit and fit a joiner and new piece of pipe.