Draw-Tite & Reese are the two major brands, can't go wrong with them.
Check out U-Haul if there's a large outlet nearby, if you don't want to do the install it can be a good source. Bought one there once, lifetime warranty if they installed it - you manage to rip it off they'll fix it.
Large RV stores can be quite helpful as well (as long as they carry trailers).
Wiring kits from either type source can be very handy. Many plug-n-play fitments are avail..
Small receiver type hitch is handy, you can remove the extension & ball when not in use. If you might want to use a rack of any kind sometime, see if a 2" receiver type is avail. to fit. Total overkill for your towing capacity, but many accessories are made for that size.
"Rubber Side Down"
S.R. #275 Focus Takeover #003