There is zero point going to the effort of migrating the content with a script if there are only 4 Topics (which appear to only have an OP?!). You are best to simply type these in again if you need them? It would take you longer to send an email to a developer!
Just start afresh as has been suggested.
Whilst running a Discourse is not “free” even as a self-hosted, self-installed owner, it is not that expensive and can be done for under $10 a month (including email service costs), especially with this little traffic.
For a small fee, you can even ask a developer to install it for you Marketplace
If you are prepared to learn, then modifying existing themes will be relatively straightforward to get a similar look.