Use the GUI view, but map the position from scene view to GUI view:
// 1. map from scene coordinates to window coordinates
sf::Vector2i positionInWindow = window.mapCoordsToPixel(position, sceneView);
// 2. map from window coordinates to GUI coordinates
sf::Vector2f positionInGuiView = window.mapPixelToCoords(positionInWindow, guiView);
// 1. map from scene coordinates to window coordinates
sf::Vector2i positionInWindow = window.mapCoordsToPixel(position, sceneView);
// 2. map from window coordinates to GUI coordinates
sf::Vector2f positionInGuiView = window.mapPixelToCoords(positionInWindow, guiView);
Great! That was exactly what I was looking for. Thanks a lot - it works just perfect :)