yes it is true there are a lot of confusing package styles and versions. Usually only a few of the many versions are available for sampling. Choose the one that you can work with-- there will generally be a surface mount version and a regular through-hole version.
Are you sure you want the MAX4851 etc that you list above? That is a different chip than the 485. Here's
a list of the 485 available packages. PDIP means plastic dip, and SOIC is a surface mount package.
The MAX485CPA+ is probably what you want for through-hole. the EPA+ has a higher temp range and they usually won't let you sample these, as they are industrial grade and more expensive.