300, 302, 303 or 307 redirect for international site?

A company website offers the same products and pages (more or less) across different countries.

It's a mess; they use a mix of subdirectories, subdomains and ccTLDs for international sites:

• us.example.com/product.html
• example.com/uk-EN/product.html
• example.com/de-DE/product.html
• example.com/nl-EN/product.html
• example.ca/product.html

They have decided to use IP-sniffing to redirect users to the right site.

Which 3XX redirect protocol is the most appropriate?

• 300 multiple choices (e.g. offer different languages)
• 302 found (originally temporary redirect, but now commonly used to specify redirection for unspecified reason)
• 303 see other (e.g. for results of cgi-scripts)
• 307 temporary redirect

I am leaning towards 300 since it makes sense, but Googlebot is in the US, so it will be redirected away from this international content in favor of the US domain?

Also, implementing hreflang is an obvious addition to any of this, but without it, which would be most suited?