I have a shimano curado bantem cu-201 really nice condition I’m buying it knowing it has a crack and I know it has a crack which got me at a discount but is there any online store selling the part BNT1507 or someone has one in good condition

ereplacementparts lists the part as discontinued, and none turn up in ebay or even google search.

Might register on Tackle Tour forum and ask there.

I'd say there is a good chance that the crack will not affect the reel's performance. Give it a try.

I would just super glue it. Just make sure using only a tiny bit so the residue won't affect the spool balance.

Or you can resort to Japan or Chinese used market. There are many merchants there disassembling a whole reel and selling parts.