Here's a link to Crutchfield and the wonderful world of wired remotes.
Remotes at Crutchfield.com
As you can see...a number of the marine stereos they sell can be used with wired remotes. Unfortunately...regular car stereos while cheaper do not come with wired remotes since it is kind of ridiculous. Many non-marine units do have wireless remotes but they are
line of sight IR type which may be impractical for your purposes. Since your need sound limited, if you can use a wireless remote I would suggest this one which also adds a jack to make it ipod or other player compatible:
Pioneer DEH-1900MP CD receiver with MP3/WMA playback at Crutchfield.com
If you must have a wired unit:
Kenwood KDC-232MR Marine CD receiver at Crutchfield.com
This is a nice unit for $149 but the wired remote will set you back another $60 bucks!
Hope this helps. What are you going to do about speakers? Upstairs & Downstairs?
DAWG...I don't believe either of the Clarions are still current models but there may still be some around and they are good units.