AC Blows fuse 17 immediately

["Colin Barfoot" <Colin_Barfoot@msn.com>]

I finally got my AC piping repaired and system recharged (with R409 a blend to 
replace R12 which isn't legal inNew Brunswick) just before leaving for 
vacation in New Hampshire (Mt Washington) Ottawa then Maine. Of course it was 
in the mid 30s Celcius and within a few minutes of punching the AC button when 
it was hot the fuse blew.  When it was cool I ran it successfully on low for 
almost an hour before selecting it high which blew the fuse.  
As the weekend went on and I drove to Ottawa (hotter and hotter esp sitting in 
Montreal in construction traffic plus rushhour) the fuse would blow within 30 
seconds of engaging the AC, though sometimes starting the engine with the AC 
on let it run for a couple of minutes.
By the end of the week the fuse blowing became immediate when the AC (low High 
Auto or Defrost) buttons were pushed.
Before I make my appointment with the AC tech does anyone have ideas.
I spoke to Chris of Autobhan briefly at Mt Wasington and he thought it sounded 
like the compressor $$$?  Does anyone have opinions or a best price place to 
buy a replacement compressor if that is indeed the cause?
TIA
Colin
86 5000 CD Quattro
307,500 km