Stereolab—the London-based, English/French quartet that rose to epic heights in the ’90s—pioneered avant-pop. They disbanded in 2009, but return now with a reunion tour and gargantuan reissue series. Seven albums will return in limited edition vinyl and CD iterations, each with a hand-numbered strip from the original master-tapes. Demo tracks, alternate takes and scrapped mixes also accompany the releases. The first, “French Disco [Early Version Mix]” offers new life to the original “French Disko,” initially released in 1993 as a Flexidisc single. It arrives electrified and dance-ready.