Mimic what you see on TV
Specifically, when the on-court sportscaster interviews a coach during the game on the court, you don't normally see a camera-mounted or shotgun mic being used. You see a handheld, dynamic, mic being used. Their common mics are BeyerDynamic (like the M58), Electrovoice (like the 635) and Sennheiser (like the MD46) among a few others and they shove the mic in the coach's face. This gets the mic element *close* to the audio source. The mic body is long so the person holding the mic gets a bit of a "boom" capability and the "mic flag" ( http://www.bhphotovideo.com/c/buy/Mic-Flags/ci/8666/N/4223241178 ) fits and there's still a handle to hold the mic.
Whether the mic is wired or wireless will depend on your budget and your definition of "audio quality" and potential impacts.
The above mics use an XLR connection. Your HDR-PJ760V has a 1/8" (3.5mm) stereo audio input and Sony-proprietary AIS. To *properly* connect a XLR mic to a camcorder with 3.5mm audio input, use of a XLR adapter is needed. I use juicedLink CX237 or a (no longer made) BeachTek DXA6. If only one mic is used, there is a "M"ono/"S"tereo switch that in "M" mode has the single mic's audio recording to both left and right channels. Also, the XLR adapter has audio-gain knobs to control the recorded audio level (that is buried in the touch screen of the camcorder - a bit of a challenge to use).
There are other "robust" less expensive, good, XLR dynamic mics like the Shure SM58 (and others from Audio Technica, Sennheiser, AKG and others) but these mics are short making use of a mic flag while holding the mic is a bit challenging.
Another option is to use a dynamic mic that uses a 3.5mm connector. The small 3.5mm connector *could* break in the camcorder's audio-in jack. They are usually a mono only so only one side of the audio in the camcorder will record - this can be dealt with during editing. These are generally consumer-grade. I don't use them, so I can't speak to their build quality or audio quality.
Again, check what we see on TV. A person holding the camera aims the camera at the interviewer and coach. The interviewer directs the mic to their mouth or the coach's mouth depending on who is speaking (no shotgun mic). I presume you won't have a camera person, so use a tripod (your camera person) and you stand in front of the camera holding/directing the mic - and do the interview like you see on TV. If you need to see what the camera is capturing (see both of you in the frame - a "medium" shot" should suffice), flip the camcorder's LCD so you can monitor from the front of the camcorder.
If you decide later, it is possible to turn an XLR wired mic into a wireless mic. Not so easy with the low-end mics, but kind-of-sort-of possible with certain low-end manufacturers.
A shotgun mic would be more useful for an interview without the court/background noise.