To my knowledge, there hasn't been a Rescue Solo comic. But the comic world is vast, and new ones are constantly emerging, so it's possible it exists but isn't widely known.
The Solo Leveling comic is indeed finished. It had a definite ending that concluded the various plot elements and character developments. Many readers are still discussing and cherishing it even after the finish.
Han Solo isn't derived from a comic book. His character was created for the Star Wars movies and expanded upon in related media, but not from comic book sources. The Star Wars universe has its own complex development process that doesn't rely on comics for Han Solo's origin.
The number of Solo Leveling comic books can vary depending on editions and reprints. It's best to refer to the publisher's information or dedicated comic book catalogs to get the exact number.
There are several options. Some people find it on dedicated comic websites. Another possibility is to check out apps specifically designed for comic reading. But make sure to use legal and authorized sources.
It depends on your taste. If you're a fan of Harley Quinn and enjoy solo character-driven stories, then it's likely worth it. The comic might offer unique perspectives and adventures.