Hi Paul
Welcome to the forum.
You pick up a very nice boat.
As for brushless motors a Hobbyking B28-57-17L 1700kv which is a 28mm motor that looks like a straight change over.
Prop a 2 blade 32mm 1.4 pitch .
Lipo battery a 3S(11.1 volts) about 2650mah.
You will find a number of different sizes on the Hobbyking website.
Harry Smith
The standard size is about the same as the old car NiCad batteries.
ESC (speed controller) a little Hobbyking car 45A (HK-45A)(69 grams) will suit that motor.
As for Lipo battery chargers get a good balance charger one(check you local club to see what the members use).
A safety charge bag is a must !!!!
I used this setup in my 25 and1/4" Aerokits Sea Hornet.