With Cristal you nearly got it with Freixenet - it's Castellblanch. And the reason you won't find it on their website is outlined here:
http://www.rtvvilafranca.cat/noticie...ellblanch.html
An EU tribunal decreed that they couldn't register a cava with that name. I'm sure I don't need to explain why

Cristalino is a different cava to Cristal and is from the Jaume Serra winery
website here: http://www.donsimon.com/
press 'family wines', 'our wines', then select 'A.O.Cava' to find a description - more in the Spanish page, there are at least 5 kinds
It could be that most of this cava is exported to the USA, I'd never heard of it either (even the online shop for the family of wine brands that Jaume Serra belongs to won't sell it to you)