I seem to have an uncomfortable time working with Lua than I do with C#, is there any available bindings to work with C# on ROBLOX rather than Lua?
No, your going to have to stick with Lua. ROBLOX was made in C++ anyways. Even though I wish ROBLOX let us utilize another language or multiple cores to run Lua code on, that is not the case and Lua is generally fit for most Operations if you know how and when to optimize your code.
Raycasting for instance is linked directly to roblox's source code to speed up such Operations, so you won't have to be stuck entirely with Lua - there are some things ROBLOX has added to the API that help a lot.
Why do you feel "uncomfortable" working with Lua? It may not be C# or as fast but it's still powerful.
If ROBLOX cannot suit your needs for game development I suggest you move to a more professional engine such as Unity3D which let's you use "UnityScript" (Modified version of JavaScript it seems) or C#.