Hi Ron, and welcome to the forum. Unlikely anyone will have a Dido for sale, and it may be that you could make one yourself. There are a few easy plans out there and I am sure that Glynn Guest must have done one in the past. glynn’s plans are very easy and with minimal effort should give you a reasonable representation of the ship.
It depends really on the level of detail you require, but likely your dad will mentally fill in the details on even a simple model. Just pay attention to the paintwork.
Ashley