Many ways to do it if they are thru hull here's a photo sequence of what I did... Also use the search feature for scupper repair etc. Lots of documentation on here...
http://s261.photobucket.com/albums/i...pper%20Repair/
You can get the brass tubing and the Moeller Flaring Tool on line. Some guys have used pvc, stainless and even straight fiberglass. Brass tubes are About $4-7 per 1" dia. tube and about $35 for the tool. More easily found online unless you have a good marine supply store around. Some guys have made their own flaring tools out of old sockets, wood, cold steel, etc.
Make sure you really seal the wood blocks that surround and support the tubes. That is important to a successful result.