Kevin,
Not sure where you sure with this or if your rig has original brass tubing. if it remains somewhat original, the process is fairly easy. I don't know of anyone in RI although the project is relatively simple and takes less than an hour once everything is in hand so don't let anyone dupe you. Any boatyard can handle this easily.
I used brass tubing from Moeller cause thats what my '72 had, and I couldn't find any thing else. Getting them out was much easier than I anticipated. I knocked in/off the flange with a screwdriver or chisel and used a 1" schedule 40 pvc pipe and hammer to tap it out.
Dry out the holes with some alcohol and ream the holes well to get the mush out. They are held in place by a glassed in 3" cube of wood and that may be deteriorating to some degree That is often the unsuspected leak point). You may even want to over drill and create an epoxy wall liner on that block before reinstalling. As far as the gap on flange angle against the hull, it should be nominal once its snug, and the 4200 or 5200 will fill the space as you compress the flange to the hull and deck. Moeller makes a tool to flare the brass tubing ($35 or so if you go with brass) Here are a couple of links to my feeble repair (not pretty but it doesn't leak). Good luck. There are many posts regarding this topic so do a search and see what's best for you. Good luck.
http://www.classicseacraft.com/commu...scupper+repair