I got one response "80's or 90's generic machine made in Taiwan. The manual probably doesn't even have a name on it. It might be a decent machine, I don't know."
This was common to have a manual that did not have a name on it so that it could apply to the machine that had different names put on it.

Janey - Neat people never make the exciting discoveries I do.

I just noticed something. Most of the Necchi machines that I have seen since the 1950s have sans serif fonts, where as your machine has serif font. I know that many machines have been badged with the same names over the years. So I wonder if it was imported and someone just put the Necchi badge on it since that was a familiar name of a quality machine.

Janey - Neat people never make the exciting discoveries I do.

I've been able to find what looks like the same machine a couple times online, but never the same manufacturer so maybe it was some sort of clone?

I just lost a nice long answer that I lost in neverland. Arrgghh.

I would consider your machine a badged machine rather than a clone. I have a machine called Miracle, but there are very similar machines that have different names that I posted about at https://www.quiltingboard.com/8414225-post15.html I have also seen a machine with the same name, but made by different companies.

Dressmaker, Kenmore, Minnesota and Nelco and many other names were made by a variety of manufacturers.

It looks to be a good solid machine. I'm not sure which check spring that it needs, but you can probably find one that will work.

I looked for a similar looking one, but could not find any quite like it. I'm guessing that the ones you found probably had a different name or maybe no name on the machine.

Janey - Neat people never make the exciting discoveries I do.

Looks like someone did something unkind to the check spring. I expect it will require the tension unit to be dismantled and a new check spring installed.