My all time favorite (at least so far) is the Billecart Rose, but I think that is out of the price range of the OP. We drink some american sparklers and enjoy them, but I don't know how available they would be in Europe...we have liked the Gruet, from New Mexico (weird location but nice wine) and the Iron Horse from Sonoma; also, a number of years ago I got a Cloudy Bay sparkler from NZ in London, and it was terrific. I have had a lot of cavas in Spain when travelling on business, but honestly can't remember the names of them, but found them enjoyable and light, especially in the hot weather.