Should I upgrade my TT wiring?

Make that Pioneer PL-518

Cannot be sure that you will notice anything but a slimmer wallet.

I'd agree with Fuzztone, although you don't mention what cartridge you have, if it's the near or the same age as the table, spend money on that first. 

@1111art  - You might do better to have KLE Innovations Classic Harmony RCA ($48) or Silver Harmony RCA ($72) plugs installed on the existing cables and you will hear an improvement.

Regards - Steve

Or spend $500 on a new turntable....  Seriously, unless you are in love with the TT, the $100 is 1/5 the cost of a new and quality turntable.   

I am a little confused.

A TT Wiring would be a Power Chord ?

A Tonearm Wiring will be mostly a Internal Tonearm Wiring Loom within a Tonearm Wand, which will have a added Tag Wire Interface at the Headshell end to connect the Cartridge End and a Phono Interconnect Interface at the  Pillar End to connect the Wiring to the Amplification in use.

As the inquiry is referring to the RCA Connectors I assume the Cable at the Pillar to Amplifier is to be the cable that is an upgrade.

Is this a 5 Pin DIN to RCA Cable ? or is the RCA Female attached to the TT's Plinth and a RCA > RCA Cable is able to be used.

In either case there are endless options at a broad range of prices and the used market is well worth an investigation as well.

Limiting the choice to an offering from one individual will not enable to see how different Cables used at the Interface can impact on the performance, and be considered an upgrade to the ones being replaced.

Does the Cable Builder referred to have a assembly that can be offered for a trial/loan period ?