It's an Intex 54497, which is a Walmart model -- possibly Walmart only.

However, the 2500 GPH filter listed on the Walmart page takes the "B" cartridge:
Unicel C-5315 Replacement Filter Cartridge for 15 Square Foot Intex B Filter @ Amazon

However, just be sure, check the measurements on one of your existing cartridges: it should be 5 3/4" diameter x 10" long