If you download Mavericks (OS X 10.9) from Apple, you will get the most up-to-date version, which is 10.9.5.
There's no reason to do 10.9 first.
It's not as simple as purchasing through the App Store, as it is no longer available as a new purchase. (I use the term "purchase", even though the software is free, you still "purchase" free software from the App Store, and OS X installers are no exception to that.)
So, you need to discover a source for the Mavericks installer. Some folks have luck by asking for a copy at an Apple store, but that may depend on who you talk to, and how nice you ask
😀
You CAN purchase OS X installers on eBay or Amazon. I don't know if you can trust those (or not), but they are available.
Amazon example
here ...
eBay example
here ...