From an EBike project which never happend I have many NESE modules 8P.
They are in Germany right now but can bring the to US and ship from there.
21700 - 8P is 13 Euro per module + shipping
Have 14 of these
18650 - 8P is 11 Euro per module + shipping
Have 28 of them
21700 - 2S/4P is 15 Euro per module + shipping
Have 28 of these