Best way to replace the elastic waistband in Patagonia Baggies shorts?

Best way to replace the elastic waistband in Patagonia Baggies shorts?

I have a pair of green Patagonia baggies that are about 10 years old — they’re super comfy, totally functional, and still look fantastic. Unfortunately, the elastic waistband is completely shot, so the drawstring is the only thing keeping them up. I’m not ready to retire them yet, so is it possible to replace the elastic in that waistband?