Second the view about Hathway (not Hathaway!). Jimmy Moon in Scotland does some good work. A place to look and buy might be Trevor at the Acoustic Music Shop in Brighton; he usually has a wall or two full of mando related stuff. Be careful about stringing a 'true' mandola (i.e a big mandolin designed to be tuned a fifth below a mandolin at CGDA) as an octave mandolin; GDAE an octave down can make the bass strings very slack, and prone to rattles and twangs. There are short scale octave mandolins about; look out on ebay for things like Fylde, Moon, Trinity College, Musikalia and Hathway. There are bargains to be had. Another option might be to import something from the States. Johnson make a fantastically pretty instrument with an asymmetric body see this one for details;
a href="http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=10179&item=3764477637&rd=1&ssPageName=WD1V">http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=10179&item=3764477637&rd=1&ssPageName=WD1V I've played one of these, and it was geat.
Tim from Bit on the Side