It will cost you around £900 - £1000 to upgrade your 330 to an ES.
Your GPS and a 330 ES will not transmit SIL = 0 so is you are flying a permit aircraft you can not play. Your cheapest option is to sell the 330 ASAP (before ADS-B becomes more widly known) and fit a Trig or similar. Again assumeing a permit aircraft.
Rod1