If you are in Sydney area go to Kite magic
For 30 dollars the owner sewed 5th line attachments in my 2004 15m and 20m. He reinforced it on inside and did a professional job with triple stitch when closing the leading edge and best of all, he sewed in a ring on to the webbing on both of my bars for the line to pass thru so that I can release the bar and retrieve and not messup my spinleash system.
It is great for the 20 as when you have a big light wind kite in light wind, it is very hard to get them to flip over.
For the 15m I added a cleat system so that I can trim the leading edge, it has helped the kite retain its shape so that it is less likely to deform when hit by gusts. It is a good inexpensive way to go if you are not ready(or too cheap) to upgrade to a new kite.