Check and call looks right to me.

Maybe this could be played like a blind steal, raise your mighty 3s since they may be best but are very vulnerable. It's harder to push the BB out since it's not two back to him but what is his image of you? The raise is to protect but it has the appearance of pressing/representing a bigger hand. Will he respect your raise since it is obvious that you could have limped cheaply instead of raising? Is the CO being lame by limping or being tricky enough to dog a big pair preflop (probably wrong since his position suggests he has less anyway and he is likely to get played back at if he raises)?

The way you played it (getting 5:1 to flop a set) is fine but the implied odds are probably less than standard situations since there are fewer opponents and a smaller pot (less reason for them to stay if you hit and they miss).

If the two lines run close in value is there possible future value from the image created by taking the more aggressive course? My experience in ring games is that people give me a lot of respect when I play full-blown poker in short-handed situations in contrast to my tight preflop play otherwise.