Mermaid figurine on table 3D print model

hello, i download the file. Yesterday, i went to 3d print company and told them to scale to 5cm hight. i'm a jewelry craftwomen and i want to use this model as a pendant. thickness is very important becouse i use valuable metal so it costs very expensive. When we scale the object to 5cm, it weighed 12gr. It is ok for me but When we make it 5cm long, the thin part just above the tail is almost 3mm thick. So the product looks very thin compared to its length. Is it possible to just widen the width a little for 5cm length. i'm looking forward to updates. thank u in advance