Maybe I am missing something, but this change seems as though it will be felt much more socially/culturally than economically. I don't see trade between Britain and the EU changing a whole lot. No doubt Britain will simply join the ranks of Norway and Switzerland who are part of the EFTA and the EEA which means trade should be business as usual.
The economy will probably be affected by their more stringent immigration policies, but not in any major way that I can imagine.
I think markets will rebound quickly and completely. That's just my take though.