Patches

Most USSS-related patches available for collection are completely unofficial.  The only exceptions to my current knowledge are: 1) Uniform Division (UD) shirt (white) and jacket (black) patches, which are simply the Great Seal surounded by small stars in a circular fashion without text, 2) the exceptionally rare (because of high accountability) USSS gold shield patch (no background border outside the shield perimeter) harvested from a USSS "raid" jacket or cap, 3) various generations of UD K-9 patches, and a couple of other exceptions that you will not find on Ebay.  Of course, none of these items confer any authority without photographic credentials.

Because of the very rare availability of genuine USSS patches-- even to agents (agents have no uniforms and hence no official use for any sort of patch other than police identification on warrant gear)-- agents have in the past commissioned custom-design patch lots out of their own pockets bearing the "Service Star", new or old, to answer the problem of not having anything to offer up for trade to collaborating local police officers in their extensive global travels.  Though quite cool and collectible, they are completely unofficial, and the only way they can be said to "come from headquarters" is if someone physically brought it out of the HQ building.  They are not sanctioned nor issued by the agency.

Finally, beware of auction listings indicating a presidential-related function, such as "photographer" or "Air Force One" correlating with Secret Service or Police in any way.  This is blatantly fraudulent.  The USAF maintains AF1 security and operations and the USSS has very little to do with that, for example.  A white house photographer is not a police or SS authority.  Similarly, certain dedicated USSS "details" for which patches are listed DO NOT EXIST.  Example: "advance detail" (ad-hoc assignment, not a dedicated detail), "Air Force One detail", etc.  Relatedly, beware of auctions that indicate that certain items are "presidential"; for example, official-looking government cufflinks.  If they do not have the Great Seal of the United States, they are not "presidential" in any way, shape, or form, no matter the US government agency.

Frequently, prices are driven up under the guise that a certain patch is "official".

Pins

There are many excellent collectible USSS event- or detail-related pins available, and these are collected by agents/officers just as much as by members of the public.  But official USSS lapel pins are controlled ABSOLUTELY.  NO official USSS pins will ever appear for sale.  Mere possession of these by unauthorized persons would lend the holder to federal charges.  These are strictly for rapid recognition of authorized USSS personnel but are not a substitute for personal knowledge of colleagues and display of proper credentials.  Relatedly, there was one seller who recently attempted to auction a close facsimile of a Special Agent shield, and the item mysteriously disappeared... no "auction ended", or "item closed".  Poof; it just disappeared into thin air.  Do you think that the USSS merely called the auction off and left it at that?  Probably not.

On the other hand, the pins that you see on EBay are pins originated by agents for trade between field offices reflecting local tradition (the Big Apple, for example), or detail-pride.  These pins may also, like the patches, be swapped with collaborating police officers for example, for an NYPD PBA/DEA pin.

One set each of official USSS detail pins is signed out only by assigned agents/officers prior to a detail, and signed back in at the end of a detail.  STRICT accountability is followed, and official detail pins or designs are never recycled.  So don't be fooled into thinking you're getting a hallowed, official "earpiece and cuff mike" pin.