I'm assuming that most US investment in Canadian stocks is still via the Toronto stock exchange through their US broker.
The PGDIF is just an entity denominated in US funds who wish to trade that vehicle.
I can buy US stocks on the New York stock exchange through TD Waterhouse with no problem.
In fact, when Miramar Mining was approaching takeover...I was dipping into the Call options in the US for the MNG symbol.
Did 2 cycles and when they announced the takeover after the first cycle of options expired. Those options broke even...the shares I had on the other hand...made lots of $$'s.
Looking for the same with Peregrine.
EKIM