The chances are, that most, if not all of them will have been manufactured in only one or two factories, certainly, as far as I know, Seig make at least two, ,if not three, of the machines on the market.
The price difference may be because of different specification, such as the accessories supplied with the lathe.
What comes, as part of the package with one machine, may be an optional extra on another
So decide what accessories you expect to need for the machine, and compare the cost of such a package from each supplier. I E. My big lathe came with a worklight. Another supplier of the same machine, will charge and extra £30+.for it, as an extra.
Different powers quoted for the motor may be that one importers quotes the input power to the motor, whilst others may quote the output power of the motor; which is what drives the Chuck!
Also consider the after sales service.
You may need it if there is a problem, if only for advice. Sadly, not all importers are equal in that respect
I wanted to convert my mini lathe from digital read out to old fashioned manual dials.
The original importer, eventually, quoted a price for the parts, plus half as much again for air freight, that was twice the price from my favourite supplier who delivered within a short time. And, both sell machines from the same source! My favourite supplier, if I want to buy something which he knows is not suitable what I have in mind will advise against it, to the point of declining to supply. He would rather lose a sale than have an unhappy customer complaining to their friends! Which is why I deal with him, and am by no means alone in being happy with, and recommending this company.
Howard