Antique Badges Wearing Of Outdated Military Insignia?

Wearing of outdated military insignia? - antique badges

I have now bought a jacket, USN (circa WWII) from an antique shop in a raid on a price. The rating badge is still attached to the second sleeve (3. class pharmacist before 5/31/41 spent), and I thought I should delete it ... But even though I already know of the uniform rules and federal laws for the use of military insignia, I have no idea if this is to use a breach of these laws and regulations and / Obsolete / badges. They do not prefer to delete them if you do not need - I have tried to find out, if we let them go, but without success. This is totally new to me, and I want to be sure.

So - Is it permissible to use outdated / old badge? However that may be, please give a source, if possible. Thank you in advance.