Based on this product's specifications, here are some alternatives and similar models
Cooling Insert for Personal Blender TEESA TSA0079 (compatible with TSA3538)
Summary description:
Cooling insert designed for TEESA personal blender model TSA3538. The accessory (MPN TSA0079) is intended to be chilled before use to help keep blends cold when preparing smoothies, shakes and beverages in the personal blender cup. It serves as a removable cooling element to maintain lower temperature during short-term storage and consumption.