Based on this product's specifications, here are some alternatives and similar models
Watch case Spigen Thin Fit Transparent Polycarbonate for smartwatch, 37×11×42 mm
Summary description:
Spigen Thin Fit is a transparent polycarbonate protective case designed for smartwatches. It fits devices with outer dimensions around 37 × 11 × 42 mm and is supplied as a single piece. The rigid PC shell shields the watch body from scratches and light impacts while preserving original appearance and touch access to controls and sensors.