I'm wondering if anyone could advise on how to patch up a largish sleeve tear in an eVent jacket?

I've had it duct taped until now but want a permanent fix - an $80 quote scared me away from the pro repair shops.
I imagine I'd need to sew on a patch and seam seal it, but eVent is not publicly available - what's an appropriate material to patch with?
Jacket is a pretty new Macpac Traverse.
Thanks