[Q] Chinese Dual Sim Version ROM help. topic

Hi, I am in dire need of help right now. I recently purchased a HTC One M8 from china (Dual sim) and wanted to convert it to either the international version (with htc sense) or the GPE.
However, all the custom ROMs I have tried don't seem to be working. My phone is rooted and the bootloader is unlocked, but it is still S-On. I'm not ready to pay for sunshine since I'm not confident that it will help my situation.

Currently my phone has no operating system according to the bootloader, and I have been unable to boot into any custom ROMs I have installed.
Being the dual sim version, there is next to no stock or custom roms to be found on xda developers, so now all I want is to revert it back to its stock rom. (I stupidly forgot to back things up before flashing custom recovery and custom roms.)

Can anybody out there help me find the file(s) I need? I don't care if I have to live with no google apps, but if someone could help me out there too that would be awesome :)

Not sure if this info will be useful, but my bootloader says:

*** TAMPERED ***
*** UNLOCKED ***
M8_DUGL PVT SHIP S-ON
HBOOT-3.18.0.0000
RADIO-1.19.30306251.17_2G
OpenDSP-v38.2.2-00542-M8974.0311
OS-
eMMC-boot 2048MB
Jul 17 2014,19:12:07.27809

My Phone's CID is HTCCN703, and I have TWRP v2.7.1.0 installed, since the newer versions didn't work.

I'm relatively a newbie - I've done this rooting/flashing custom rom stuff on 3 or 4 phones before but never ran into any trouble, so help would be greatly appreciated.
Thanks in advance, and I apologise if I'm posting this in the wrong place, or if someone has asked the same/similar question before. If that's the case please direct me there :)