Lucas,
The other day I was on my tablet and it is usually hit or miss whether my posts will post to the forum. Here is my information on using oars with my DSII which is not that much different than your boat. I installed oars on my boat in 2010 for use as auxillary power while sailing the Texas coast on the Tx200. I didn't want to carry gasoline for an outboard and I felt the boat would be loaded heavy for 5 days of sailing and I decided I did not want to use a heavy battery for an electric motor. So I decided to put oars on my boat like many of the other small boats on the event. I had initially tried paddling the boat with poor success. I had seen on this forum that a few others had added oars, so that I decided would be my course as well.
The oarlocks are placed in line with the mainsheet attachment at the aft end of the centerboard trunk. I installed 4" inspection ports to bolt my oarlocks to the boat. I placed my ports forward of where I wanted my oarlocks with the idea of being able to access my jib tracks as well. My mistake was using a 4" port and placing them forward. The port should have been a 5" (maybe 6") rather than 4". The 4" port is too small to work with. The port also should have been dedicated to the oarlocks.
The rowing seat I made was from 1x8 or a 1x10 board (can't remember) that was cut long enough to span the width inside the cockpit with the ends supported by the seats and the center supported by the centerboard trunk. Because of the angle of the seat tops I put small blocks on each end to deal with the angle. In the center I put blocks on the board on each side of the centerboard trunk to keep the board centered for rowing. There are posts on the forum concerning oars and some better rowing seats than mine.
The oars that I am using are too short, only about 7' long (it was all I could get at the time. The oars really need to be about 8.5' long. I originally stored my oars along the cockpit on the side deck to keep them out of the way. I attached harness staples that would use 1" nylon straps to tie them down. Problem was that the oar would foul the jib sheets while sailing. I moved the oars to the inside of the cockpit storing them at the base of the seat and the cockpit sole. As I recall this is long enough to accomidate about an 8.5' oar. On the stern end I installed a loop to fit the blade in and about 2/3 forward of the stern I installe a staple for a 1" nylon strap to secure the oar. With one securing strap and the blade end in the loop it is easier to get the oars out when needed. When I have the boat heavily loaded for camp cruising, I store the rowing seat in the stern strapped down across the seats, sometimes with a solar panel mounted above.
The DS will row well with maybe about 6" of centerboard down to help the boat track and to reduce rocking. I suggest having a topping lift to keep the boom from hitting you in the head while rowing. I tried it without a topping lift, no fun.
These days I also carry a 2.5hp LEHR propane outboard. According to the manual, a one pound cylinder (short green propane cylinders) will last 57 minutes at full throtle. From use, I would say that is correct, longer when not a full throttle. Changing cylinders is fairly easy and quick. The motor can work with an external tank as well. When putting the motor up, just pull the cylinder out. The motors have the noise of a standard outboard, but not the odor.
For rowing hardware, you might want to check out Duckworks
http://www.duckworksmagazine.com/ For anything Day Sailer I strongly recommend D&R Marine.
John