I'm a little liberal when it comes to the definition of "Open data", and many people may not agree....
But, I consider "Open" to be more about accessible and machine readable. For example, a common business model is to offer free API for requests within a quota, and offer a paid service for unlimited. An answer with this data source would not be deleted, unless it was self-advertising or the free-tier wasn't practically useful. The data source doesn't qualify as "open" in its fullest definition.
Another grey area is where the data owner requires registration to access the data. That's not "open", but the answers are allowed here.
Or data without a fully open license. (It's important to point out if the license sucks.)
I think you should ask your question and not mention that you are willing to pay. The answers may include some resources which offer paid, extra services. If you are only willing to buy data, then probably your question is not right for here.
In general, I think questions should be asked, and then answers rated based on how useful they are. Instead of deleting low quality answers that are not spam, I prefer to downvote so they are hidden from view, but still technically available.
Note: Making a new site is challenging and requires community momentum. Before making a new site, I'd try asking on a more commercial platform, like Quora, which requires registration to read more than one answer.