Hi Kevin,
Sorry to hear about you wife's leg I hope she is healing quickly.
My wife and I have a 2003 R21 classic, (not-extended cabin) that we got this year. Though we are new to the boat, so don't have a lot of time with it yet, we love it. Relatively simple, and very economical to operate equals more time on the water for us.
I do not hold myself out to be an expert but I will share what I learned on my recent R21 hunt. 2006 seems to be the year the last R21 Classic was made and the first R21EC with the extended cabin appeared. The Classic has the shorter cabin and tends to be a little more spartan in its finish. Many of the R21 classic owners opted for the mast that steps just behind the pilot house most often used to rig a sunshade, but I have read (never seen one) of a steady sail rigged there also. At the time Ranger extended the cabin, they also modified the hull a little bit by adding a "step" in running across the hull in the area just above the prop. This was done I presume to add volume back there and keep the boat from squatting as the speed increases and up the cruise speed. They claim that the ECs cruise at 8kts, I am sure you can get tons of verification on that from the 21EC owners on this site. My Classic likes 6 knots. It seems to hit that at between 2200 and 2500 rpm. I can go to max power (3600 rpm on my 27hp Yanmar) and I burn more fuel, make more noise, and get a whopping 7.8 to 8 knots.
That's one thing about these boats, they are displacement hulls and, like a keel sailboat go at hull speed. You have to be ok with that or this is not the boat for you. If you are a former sailboat owner (me too) the speed is just fine, and to me preferable. If that is the not case, try a C-Dory. They are great boats too and worth a look if you need to go faster.
Notes on looking for these boats: My gathered knowledge only, so...
Start here. There are 2 for sale on this site. I think Ron Cowans boat was the last Classic made in 2006.
Boat Trader on line lists many, there is a company named Ranger that makes bass boats (lake style fishing type not cutty hunk bass boat). There are a ton of those on the market and can cloud your search results. It can be helpful to search for a Ranger manufacturer with a min length of 21 and a max length of 21, that weeds out a bunch.
These were also known as C-Rangers for a while (not sure when, years) due to a marketing arrangement with C-Dory. So you can search for that too.
Use of the Key word "tug" can help.
Through looking at adds on online I learned that there is a dealer in NY:
Coeymans Landing Marina
20 Marina Drive
Coeymans, NY. 12045
1-518-756-6111
www.coeymanslanding.com
I know nothing about them and have never had any contact with them, just giving you the info.
Hope this helps, we love ours.
Dave