good quality radio controlled boats that don't cost a fortune?

So I’m thinking ahead to possible presents for the Piper Cub, and one thing that occurred to me was a radio-controlled boat, since we live near a lake.

Then I went googling, and found web-sites with radio-controlled boats that cost a fortune (like one for a Titanic model going for a mere €899). It looked like a hobbyist web-site for people who wanted to build their own customised boats.

Is there a place to get radio-controlled boats that are more at the toy end of the scale, so to speak? My googling has not been productive.