Are you trying to infect humanized rats? Otherwise, my understanding is that the only host for HCV is human hepatocytes.
the only rat model that I am aware of is transplantation of Huh7 human hepatoma cells into fetal rats by i.p. injection (Ouyang World J Gastroenterol 2001;7:324). However these are not primary human hepatocytes, and the level of viremia was low.
We are currently working in a model of humanized mice that is based on immunodeficient mouse transplanted with differentiated human hepatocytes (commercially available). This model seems to be working fine with HBV and we obtain fairly good viremia. [J Clin Invest. 2010 Mar;120(3):924-30]. Regarding viral generation of HCV you can generate it using a plasmid, in this publication the method is described [ Curr Protoc Microbiol. 2010 Nov;Chapter 15:Unit 15D.1. doi: 10.1002/9780471729259.mc15d01s19]. Hope this works for you.