There are no ROMs specifically for the I537, however...
Safestrap allows you to install (up to 4, theoretically) most any ROM out there at this point for primarily experimentation since there's only one that appears to be working properly but there's a specific sequence you have to follow to get everything working. You can find all the info you need as well as Safestrap in that thread located here:
The only ROM that's working as I just mentioned is this one, the AOSP port of the Google Edition for the I9295 (the International GS4A):
With Safestrap you can "install" a ROM that goes onto the native internal storage of the device, runs from the native internal storage, and now because of Hashcode's update has the full performance expected (all 4 cores recognized and working).
I currently have the stock MF3 ROM (the AT&T junk) install as expected, and then I installed Safestrap (updated to the newest one released on Sunday morning), added it as a recovery method, created a new slot (of the 4 you get) for the AOSP ROM, grabbed the ROM itself, the MF3 kernel modules which get the actual hardware like Wi-Fi and Bluetooth functional (of which there are MF1 modules for the MF1 stock ROM available too), then the camera fix zip created/shared by LeJay to get a working camera. No you don't get all the Samsung additional stuff like HDR "Rich mode" shots, or a lot of customization at all but the camera does work for regular pics and video recording.
It runs very well, posts benchmarks well past the standard GS4 (meaning using stock ROMs for it), and the HTC One as well so it's great.
Currently in between devices...