I just bought an aluminum 12' flat bottom boat, and until I get it licensed, I'm going to need to be rowing around. However, I'm not sure how big of oars I should buy. I feel a little silly asking this question because I actually have quite a bit of experience rowing, I just have never had to buy oars. The boat is 3' 10" wide where the oar locks are at and somewhere around 2 feet deep. Thanks in advance!