For a completely custom connector, that seems like super cheap NRE to me. I work as an EE and have paid more than that on small run prototype stuff that is simp

For a completely custom connector, that seems like super cheap NRE to me. I work as an EE and have paid more than that on small run prototype stuff that is simpler to manufacture than a connector (think prototype circuit boards). Connectors require multiple sets of tooling and specialized processes unique to the connector industry. Even getting the tooling for the simplest plastic part is goig to be thousands of dollars.