Dolmanger,
The FI injected version of the Lycoming 320 block is already available. As heli-mad rightly says, the same engine is already being used in the S300cbi.
However, there is a considerable cost and hassle of certifying a new engine in the old airframe. I don't have the exact numbers but if you are lucky, try asking Robinson who much it cost them to certify the R44 RavenII. (ie essentially a FI Lycoming 540 into the Raven airframe.) But that process made sense - look at the numbers of R44RIIs that they are currently selling.
There might even be the problem of having to re-design the drive train. Although FI doesn't technically give you more power, FI engines do tend to be more powerful. Could the current drive train handle an increase in power? Unlikely.
And then there is the further issue of adding further weight to an aircraft which is already on the limit of it's usable dry empty mass.
So, to my mind, these issues all add up to the R22 either staying carburettored or going out of production. Especially for a company which is currently focusing on squeezing a turbine into a slightly swollen R44 airframe.