Well here it is... the finished item.  My brother went back this afternoon to celebrate New Year with his girlfriend and other friends, so I grabbed a picture of it before he packed it. 

The size was fine in the end... a big relief!  It was quite a labour of love, but enjoyable nonetheless.  He reckons he'll wear it around at work (he's a geologist and works in a University Geology department)!  I'm sure he will, and I wouldn't be surprised if some of his friends decide they want one too.  They're a mad bunch.