Expression of amazement:

"Well, I'll be dipped!!"

In what? Well . . . I guess you just have to use your imagination.

And then there is a long list of great curses from the Middle East, such as "May wild asses defile the grave of your grandmother!"

And another, this one from the Jewish tradition:   "May you have a hundred mansions. And may each mansion have a hundred bedrooms. And may each bedroom have a hundred beds. And may insomnia keep you bouncing from bed to bed all night!"

Of course these are more in the nature of curses than swear words, but they don't use non-G-rated words and they require a certain amount of imagination to construct.

Don Firth