It’s been only four months, but Paris Hilton is telling pals that she’s finally found Mr. right in her Swiss businessman boyfriend Thomas Gross. “ever since her sister, Nicky, got married [to banking heir James Rothschild], people have been asking Paris when she’s going to get engaged,” says an insider. Indeed, Paris herself began dropping not-so-subtle hints to her 39-year-old beau — who’s worth an estimated $200 million — that a giant diamond ring would look “so hot” on her ring finger. “Paris wants to walk down the aisle sometime next year,” explains the source. “She’s turning 35, and she’s ready to settle down. She’s even talked about being a mom. Nicky is planning to have kids soon, and Paris loves the idea of them being pregnant at the same time.” Plans for Paris’ fairytale ending seem all but certain, except for one small hitch: taking thomas’ surname. “No way does she want to be called Paris Gross,” laughs the source.