SS Wheel Building

[HLaB]

Due to total lack of maintenance the Free hub on my SS fell apart today after circa 2,750 miles. Given the bike only cost £175 and where I leave it, I'm loathed to spend too much on it.
I could keep it fixed but I think I prefer the free when dealing with random SMIDSY's.
Looking at hubs Winstanley's due what looks like a nice sealed free hub. What dimensions do I have to look at before ordering and is building a SS rear wheel difficult?

 

[HLaB]

Or this seems to offer a middle ground, I think I could just screw it on ?

 

[Christopher]

If it is just the freehub that is goosed than why not replace it? After all a new wheel will set you back at least £50 in parts... by the way make sure you can unscrew the freehub - I had one i could never use as no lbs tool i could find would fit it...