It's possible the injector could be clogged or malfunctioning, and that
would certainly cause a mis-fire.  Yes, they can be replaced pretty easily,
and you can replace just one.  To do so, you'll first need to remove the
pressure from the fuel rail - either through the test port (middle on
driver's side) if so equipped, or simply pull the fuel pump fuse and run the
engine until it dies.  Remove the electrical connector from the desired
injector, then unbolt the driver's side fuel rail from the manifold (couple
of bolts hold it down), and gently rock it to free the injectors from the
manifold (they're just pressed in with O-rings around them).  Don't lift too
much, because the electrical connectors on the other injectors are still
attached.  If they don't provide enough slack, disconnect them as well.
Remove the clip that's holding the injector to the rail, and remove the
injector.  Put the new one in (lube the O-rings with a little petroleum
jelly, so they don't tear - lube the O-rings on the other injectors, as
well), re-install the clip, seat the rail back into the manifold, bolt it
back down, plug everything back in, and you're all set.

Before buying a new injector, you could simply swap say #1 and #5. and see
if the misfire moves to the #1 cylinder.  If it does, you know you've got a
bad injector.  If not, you're not out the $$$ for a new injector, and know
you need to look elsewhere (like a compression test and/or leakdown test).

Changing the spark plugs will most likely fix the problem short term.
The real fix is rerouting the spark plug wires per a Chrysler service
bulletin on cross firing. Don't remember the SB number. This is what I
did to fix my sister's 98 Dodge 1500 with a 5.2L engine that had this
code.  It has worked for over 100,00 miles now.
John