Possum, first of all, how the heck you been? Haven't seem much of you lately.
Secondly, nope, the only way to complete the "any ship" transaction is to counter offer and name the ship you want to trade to him. This allows you to trade ships with an empire when you can't see each others space and can't see the ships involved before hand. Otherwise the "sight-unseen" trade would be impossible and you would have to move the ship you want to trade into view of one of his ships and then offer it in exchange for one of his you can see.
Geoschmo