Hi,
As you stated MCUXpresso IDE do not support LPC1227, however, LPCXpresso IDE does, as you can see on the Supported Devices on the LPCXpresso IDE page
LPCXpresso IDE v8.2.2 | NXP Semiconductors
Also, IAR Embedded Workbench, Keil MDK and Keil Studio has it in their supported devices, however, I suggest you double check directly with them to ensure support of this device
Best Regards
Pablo