NPJ
The Happy Hunter was produced and sold by Robbe.
They ceased trading some years ago as did Graupner so you may find it difficult to purchase and the additional fittings kits if sold sold separately may no longer be available.
I have seen a model built professionally for a local supplier and the kit made a superb model. it is, in my opinion, more suitable for a builder with several models experience.
It's good to hear you are so inspired to take on the next challenge but this may be a step too far at present.
There is a buid post at
http://shipmodelers.com/uploads/3/4/5/2/34520124/happyhunterbuild.pdf
Good hunting