Mild SPD - How can I exercise?

[Cricket]

Hey ladies! Does anyone have any suggestions for ways that I can get some exercise without aggravating a mild case of SPD? I've been doing a prenatal DVD that I love, but it has a lot of squatting and stretching, and I'm afraid that it's going to make things worse. I really don't want to give up on exercise entirely for these last few weeks.
Any suggestions? Is going for a brisk walk, pushing a double stroller, a possibility? I imagine swimming could be ok, but I don't have a maternity bathing suit, and tbh, I really have no desire to be seen in a bathing suit at this stage of the game!