impedance matching Transformers for audio

Does anybody happen to know how to reverse engineer a pre-existing miniature audio Transformer and build a new one from scratch with identical characteristics?

 

It looks like integrated circuits are his specialty. Winding Transformers is a whole different ballgame and it's pretty much an art form.
I know the primary winding is half as many wraps or turns as the secondary winding for a 4:1 impedance ratio. Frequency response is also critical and I don't even know how to factor that into the equation

 

I've already seen some high-dollar Transformers made in Sweden for recording industry but that's just a little out of my price range especially since Telex used to sell replacement Transformers for $2.50 a piece.

 

Mouser doesn't seem to have anything that quite fits the criteria

 

Already read that Bill Whitlock book although most of that stuff went over my head.

 

I wonder if anybody happens to know where to locate a miniature audio Transformer with a 4:1 impedance ratio suitable for matching a 150 ohm element to a 600 ohm input something along the lines of this

 

I'm also looking for a miniature audio Transformer with a 2.5:1 impedance ratio for my AKG D 58 which is 240 ohms

 

http://www.mouser.com/ProductDetail/Triad-Magnetics/MET-32-T/?qs=HSwFsqQPTVP/yzTvL84Umw==



not sure if this would work