Ok, so they were after all located in Premià de Mar (some 20 km northeast of Barcelona) since always. The business still exists but doesn't appear to be actively building anything.
In the early and mid-1970s, Roga was the third most popular 470 worldwide, after Morin (France) and Vanguard (US). However, after the first Olympics of the class (1976, where Spain got a silver medal) they somehow disappeared from the race courses. They still held a builder's licence only a few years ago, and according to the then-active website they would build you a 470 if you absolutely wanted, but you shouldn't expect to win the Worlds with it... or at least that was the gist, if I understood the Spanish correctly!
There's a lot of work to do on your boat (many, many strange fittings in strange places

), but if the hull is structurally ok then it's definitely worth it. If you look at the "470 Questions", "470 Layout" and "Mid 70s 470" threads in this forum you get a taste of what's ahead. Keep posting
_