I was just going to say that. All wheel-on roller bags have a zipper for the inner lining that you can open and stash anything small and flat. I have no idea what that looks like on the airport x-ray
but I doubt your wife would ever think to look in such a place.
Otherwise, just buy them on the road. Unless you need U.S. jumbo sized trojans, you should be able to find an acceptable rubber. I've been picking up the Okimoto's on the fly, but would rather bring mine from the U.S. for size/fit issues. What stops me is the (minuscule) chance that I get searched at security. Yeah, I know, call me crazy, it's stupid.