SCLL have not disbanded at all. They have a personal life as well and deserve some rest after having released two albums at once two years ago. Also they are updating their official homepage and facebook page from time to time. If anything is about to happen, they will tell. Their last two albums were released on short notice as well. Also they have released some new songs since then and a complilation as well as a Live album. And no, they are not that big in Japan. Although, I have indeed heard them in radio and some animes.
I don't really know when it was the first time I head "sea", but after many years later, the song is just as fantastic as it once was, and in fact, most of SCLL music is just as awesome as it was years ago. But sea in particularly, such beautiful song, definitively on my personal top 5 tracks of all time.