You shouldn't let the price in euros bother you. VISA will just do the conversion for you. They will probably give you a better exchange rate than if TomTom put its prices in US$, which they would no doubt round up.
In your case, purchasing from Canada is going to require a conversion anyway.
The map prices seem to be a real bargain right now. Is there a sale on?
That's a good point, although I don't have a VISA, just MBNA Master Card and American Express.
They have a sale, according to the UK site, that maps are 50% off till the end of January.