That’s kind of hard to really answer considering how few Sansha role players there are.
First, hello. Depending on how new to RP you may be I would encourage you to take a look at this wonderful recently pinned post about getting in to RP in general.
Second, the closest thing I can think of to a Nation Loyalist RP channel would be the in game channel ‘White Morning’. It is an In Character only channel made by Sansha RPers from the corporation True Slave Foundations. While the corporation itself is currently inactive, many of the Nation RPers from that corp (myself included) are still active in the game. Though I am not currently logged in to EVE I am most evenings USTZ.
Third, lacking a real active sizeable group of Nation roleplayers to rally around if you want you can just mail me and we can chat a bit and I can give you some pointers and advice one on one. Other than that I would recommend following the first link I posted in this reply to the ‘So you want to get in to roleplay?’ thread and use the channels there to meet RPers in general both in and out of character.
Hopefully that helped.