Hi, I am out of date with current regulations for donating bodies to science, but as I understand it the universities are currently deluged by " offers" possibly due to some people thinking it might avoid the cost of a funeral.
To the best of my knowledge the request to donate your body has to be agreed by the place that has agreed to accept it and everything signed well before death takes place.
Most places will accept only bodies when there have been very unusual health issues experienced.
Also, if you donate to a place that specialises in one area of the body, eg the brain, and they accept, they will only remove the brain and any other relative bits and return the rest of the body to the family.
As Petera had mentioned, they will also not usually accept bodies that are not located relatively close by, and in direct relation to this thread, would be highly unlikely to pay for a body to be brought from abroad back to the UK.
Also, I think they can't accept embalmed or otherwise treated bodies and so if an accepted donor died abroad, and as part of the " travel arrangements" the body had to be treated, then it is likely that the donor arrangement would be cancelled.
It would seem that everyone who has been accepted as a donor would still need to have a plan b in place in case the body wasn't accepted right at the end.
I think it would be best overall if everyone travelling abroad made sure they had adequate insurance in place to cover whatever they needed to happen in the event of their death.