John,
The coupler you got is probably a diplexer - a device to feed two antennas with one cable.
You don't need a spectrum analyzer - a Hack-RF or similar SDR will do. Connect the noise source to the directional coupler input and the antenna to the coupler output. Attach the SDR to the coupler's coupled port. With your favorite SDR software tune your radio to mid-band (2.442 - 2.447 GHz). Note the receiver power level. Reverse the antenna and noise source, repeat measurement. The larger number is the power delivered to the antenna, the smaller is power reflected back from the antenna. You can use an online calculator like this
http://rfcalculator.mobi/vswr-forward-reverse-power.html to calculate VSWR. The ideal VSWR is one and an antenna with greater than three should not be used.
Although the antennas are only rated to 2.2 GHz they may be usable at 2.4 GHz. Check the VSWR.
The antennas are probably useful for hams (there's a 902.005 MHz through 927.995 MHz band). I can ask around and see if there's is any interest. You might want to put one one ebay and see if there's a market.