(Adds details from CEO, used car market, rivals) PARIS, May 26 (Reuters) - Aramis Group, which sells second-hand cars online, said on Wednesday it had taken a first step towards an initial public offering (IPO) in Paris, in a sign that stock market listings in France are beginning to pick up pace. The company is 70% owned by Stellantis , the carmaker formed by the merger of France’s PSA and Italian-American group Fiat Chrysler. It is looking to raise 250 million euros ($306 million) from the IPO. Aramis said its registration document had been approved by the French financial markets authority, which marked a first step in its IPO plans. Its founders declined to comment on the overall valuation Aramis was aiming for in the listing. German used-car trading platform AUTO1 listed in Frankfurt earlier this year, raising 1 billion euros in an operation that valued the group at about 7.9 billion euros at its debut. Aramis, which operates sites like CarSupermarket in Britain and is present in France, Spain and Belgium, said it was looking to expand through further acquisitions, as it profits from a boom in used vehicle sales. “We operate in a huge market which is switching online,” said Nicolas Chartier, who will head the group post the IPO as chairman and chief executive. The bulk of second-hand car sales in Europe still take place in dealerships and between individuals, but Aramis, which only has a 1.5% market share of used vehicle sales in a market like France, is looking to expand in a fragmented online market. Stellantis, one of Aramis’ suppliers of used cars, will not sell down shares in the IPO, the company said. Aramis is aiming for organic revenues of 1.25 billion euros in the year ended 30 September 2021, it said, up from 1.1 billion euros in 2020. Parts Holding Europe (PHE), also known as Autodis and which sells car parts, is also preparing for an IPO, after a slow start to the year for French listings, when markets elsewhere in Europe were busier.