Jim,
HPD (Honolulu PD) is always hiring, here's the HR page:
http://www.honolulupd.org/hrd/index.htm. However, Im not sure if they take transfers from out of state. All I know is a retired officer from NYPD (who was actually at the scene on 9/11) went through the academy here again and is starting out as a "rookie," even though he's a 20+ year veteran. I'm not sure of the details...try giving them an email or call.
As far as the 300 goes, cops here are allowed to use personal vehicles as police vehicles (they are given a vehicle allowance) after a few years on the force. This is to reduce the amount of maintanance and inventory that the department needs to keep on hand. However, you can only use them for up until they are 10 years old. There is a Tahoe around my area that runs around with 20" IROC replica wheels.