On Mon, 18 Apr 2011 06:03:02 -0500, DougC
wrote:

I need a chain drive: a ~3 inch cog driving a ~6 inch cog, with 7 or 8
inches in between them. I would only need one set.

I got curious about using the silent Ramsey-style chain but cannot find
anywhere that retails the chains and the cogs.

Ramsey being a brand-name of the drive chain that looks like this-
http://www.ramseychain.com/index.asp

That indeed looks hard to find. I just surfed Mcmastercarr nothing
there. Do you have super high torque needs? Otherwise, take a look at
heavy duty XL timing belt and pulleys