I manage a machine shop and quoting is one of my many responsibilities, so I'll chime in.
$235 seems a bit high, but not by much, actually. The problem you are going to run into is that you only need one part, and as I tell my customers all the time, the cost is in the setup. If I were going to make that piece on one of the CNC machines, I'd charge a minimum of $150 for setup/programming, and to that I'd add material costs ($20 max), finishing (not much), and shipping. That gets you pretty close to $200 right there. One thing to think about is that I like each of my machines to make about $100/hr, and they aren't making money when they aren't making parts, hence the high setup costs.
Your on the right track: take your drawing, both paper and electronic, to local machine shops and have them give you a quote. Chances are you can find a hungry shop to make that on a manual machine for $50-$100 (just guessing), as I see no reason that it needs to be CNC'd, especially for just one piece.
(I'd offer to quote it myself, but we are more of a production shop and generally don't do one-offs. If you need 100 or so, drop me a line
)
Good luck. You should be able to find someone locally to knock that out in an afternoon.
Jim