IMHO, all the epoxies are good, but I like the
Boat Builder Central stuff the best. It doesn't "blush" and you can put multiple coats on top of each other without waiting to wipe/sand in between coats. West blushes, MOS and BBC doesn't and BBC is the cheapest/best I have found so far. 85 bucks for a 1.5 gallon kit.
I think you are on the right road by going with the epoxy, I will never use glass again for repairs or stitching pieces together. The only problem when you use epoxy is what to cover it with. They say you can't gelcoat over epoxy, which leaves you with 2 part urethane, which aren't easy to blend into existing pieces, so you usually end up painting a lot to do a repair.
As far as matching what you have, good luck. If you want to spend a great deal of time, you can probably get close. While your at it, you might want to check the rest of the deck out for moisture, to make sure you get it all at once.