Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
Three-dimensional figures of living beings that have shadows are forbidden according to all the scholars. It is prohibited to make them, keep them or use them unless beheaded or lacking a vital organ without which they would be dead.
So, it is unlawful for you to buy gold charms for your jewelry with animal - like figures unless they are as described above.
On the other hand, we advise you to buy charms of non-living beings like flowers, trees, etc.
Allah knows best.