your cheapest option will be an OE set from ebay. ud prob pay less than 40$ shipped... too bad it would be an eyesore on a naked bike.
next best thing would be the Vapor from Trailtech. http://trailtech.net/motorcycle_vapor_kits.html all u do is mount their senor somewhere on the forks and epoxy a tiny little magnet to one of the rotor carriers, wire up the power and ground and youre set. the speedo works pretty good on this model and its only like 125$. not OE quality like on newer sportbikes, but ya. ull have a tiny bit more trouble w/ the tach, but screw it.
and the finale best possible solution to a naked bike w/ no gauges is the real Veypor... sadly, its like 5-600$ though.
Naked 93' F2...... RIP -- 04/12/07
04' 600RR Black - currently stuck between track and street usage
- Brembo Master, Sato's, & Ohlins out back