Yes, if a non-licensed seller is selling/shipping a handgun, find a good FFL dealer that'll treat you fair - say, $25 fee plus the shipping cost - and you'll get the job done for a little under $50 and won't have to worry about it being done right/legally. The FFL can even use the flat-rate boxes if the gun fits. Even if it doesn't fit the inexpensive flat rate box, the USPS shipping rate is only about $20-something.I could have shipped it for Half of that with my fee included.
For a long gun, an individual can ship via USPS no problem, and for the same cost as the FFL can do it.