I am not directly involved in this, but your claim to know regulations and directives can easily be disproven. You should maybe read CCIA Notice #7: "Uniform Regulation":
"Personnel should be reminded that regulation requires uniform jumpsuits to be worn rolled up. Tajaran crew members are excepted from this requirement, but are required to wear a non-revealing undershirt or tank top that does not bare the chest.
Uniformed security employees are to wear only standard equipment provided by NanoTrasen. Security uniforms do not include personal clothing, or items that would significantly impact the crew's ability to immediately identify security personnel. Minor alterations to uniform equipment are permitted in order to accommodate non-human species.
Personnel failing to meet these requirements are in violation of regulations, and are subject to fines, detention, or other applicable penalties."
If you wear a poncho that hides the entire uniform - you are breaking a regulation. Some people could even argue about the cowboy hat. If you, as a contractor, are not wearing your contractor's uniform while on duty - you are breaking a regulation, as defined in CCIA Notice #30, "Regarding Contractors":
"Contracted employees on board Nanotrasen vessels are fully subject to the established Nanotrasen chain of command, station directives, notices and regulations. They are to clearly state the fact they are contracted as well as their parent company, in their security and employment records. Contractors are to wear their company uniforms in all fields in order to be distinguishable, and are not to hold any internship positions. They are also not to be promoted to Interim Head of Staff positions under any circumstances."
All equipment you use or get from the station (thus, ingame) that does not come from your personal loadout - guns, tasers, ammunition and all other security equipment is all provided by NanoTrasen and issued equipment by the Corporation. Nothing besides the uniform "belongs" to the Eridani PMC and even that I couldn't tell for sure. It's not your uniform either, so you can't say it's theft.
Again, I am not directly involved, but as CCIA I feel the need to advise you that your understanding of Corporate Regulations, Directives and CCIA Notices seem to be lacking, as Nantei already pointed out. You should read it again.