Question about using circs (length)

I’m knitting a pair of toddler pants. I have 124 stitches on size 6 16" circs. I’m about to split for the legs and will have 52 stitches for each leg. My instructions tell me to switch to 12" circs but I don’t have them. Do you think I could do the legs with my 16" circs or should I really go purchase the right length?

I think 16 in would stretch the stitches too much. You could either get a 12 in like it suggests, use DPNs, 2 circs or magic loop.