Need a little help

I have had this cross fountain pen for a few years now. I stopped using it because I cannot find the right cartridge for it.

I have a Lamy Safari and looking to get a TWSBI but too many choices for me right now.

I don’t even know the name of this one. I would like to get a converter tube for it but Google has let me down so far.

Will anyone who knows a bit about this one point me in the right direction? I appreciate it.