have you tried asking straight talk to unlock it?
i believe they require a device purchased since 1/1/2014 and 12 months of service, though
i think its worth 180-240
.....
TracFone Wireless, Inc. Unlocking Policy
If you bought a new wireless phone from TracFone Wireless, Inc. (“TracFone”), including any new TracFone, NET10, Straight Talk or Telcel America branded wireless phone (“device”), it may have been programmed with a lock that prevents it from operating with other compatible wireless services. TracFone will facilitate unlocking your device upon request provided that you have met the requirements set forth below:
General Eligibility Requirements for Unlocking TracFone Mobile Devices
TracFone will facilitate the unlocking of a TracFone device under the following circumstances:
The person requesting the unlock must be one of the following:
a current TracFone customer who provides the IMEI/MEID serial number of the device
a former TracFone customer who provides the IMEI/MEID serial number of the device
The TracFone device was first introduced for sale on or after January 1, 2014.
The TracFone device has been in service for at least 12 months with paid, verifiable airtime.
The TracFone device has not been reported lost or stolen.
The TracFone device is deemed by TracFone to be capable of being unlocked.