The only issue is that you will have to decide to either export it directly into the standard OFX version 1 format or export it to an XML-conforming standard, then morph it into version 1 format.

The speed of a search is satisfactory with standard search methods (<1 second).

Part 1 of the standard (3166-1) defines two character country codes and part 2 (3166-2) defines three character codes.