for hydraulic line for power steering and LAD lines I stumped into a Porsche forum and they said
back in 2003 that http://www.stoddard.com/
"Stoddards sell all the OEM Cohline fitting and crimp sleeves. Be aware that you will need a shop with the correct crimping dies to make the hose"
and much to my joy I could even find the Cohline numbers for the high pressure hoses
http://www.newcoproducts.com/cohline/index.htm
here a pic from a power steering hose I cut off
The steel tube connectors have 250 bar mentioned/embossed

The typical procedure is to take and cut off the metal sleeve over the hose with grinder or cutoff wheel in a 4 inch grinder. Then you remove the old hose, you use a new sleeve with the old metal fittings and new hose, the new sleeve is crimped into place just like the original. I've seen some shops they silver solder the sleeve onto the original end and then install the hose and crimp but it seems like doing something completely useless to me.

Now you have to find a compant which sells the sleeves, maybe:
http://www.transconn.com/parts/index.shtml

price comparison of ready made hoses

or contact Cohline USA for a dealer:
Cohline GmbH

USA-Hazleton

Tel.: +1 570-4548832
Fax: +1 570-4548626

http://www.cohline.de/

If anyone has a source for cohline hoses by the meter and crimp sleeves, let me know. I am trying to buy a crimping tool for hydraulic hoses.
smallest and simple one will be o.k., still searching/investigating
http://www.customcrimp.com/
http://www.discounthydraulichose.com/
http://www.hpshydraulics.com/hoses.html
http://www.onsitehose.com/hose-crimping.html
http://www.onsitehose.com/samples.html