The 108-ball BGA (10x10 mm) footprint demands careful PCB layout — the 0.8 mm ball pitch is standard for a four-layer board, but the core supply of 1.235 V to 1.365 V needs a dedicated low-noise rail, not a shared 3.3 V bus.
TI (who acquired the Luminary Micro Stellaris line) no longer manufactures it, and no official last-time-buy window remains open. For production or repair, the only channel is the independent surplus market. If you need a drop-in replacement, there is no pin-compatible second source from TI or another vendor; any migration will require a board spin to a current Cortex-M3 or M4 part with a similar peripheral set.