Maternity Support Belts/Sciatica?

Laurie • Mama to daughter E (3) and son J (newborn).
Does anyone have any info/recommendations for maternity support belts? I'm only 22 weeks along, but my lower back and legs just started to be a huge discomfort. I read somewhere these might alleviate the pain. Also not sure if what I'm feeling is a sciatica, since the pain isn't necessity sharp.