Expand SATA ports via PCI/PCI-E card?

Mobo: GA-Z77-DS3H |CPU: i7 3770K |Graphics: MSI GTX 970

Hi folks, just recently lost my Mavericks install of 4 years (couldn't fix a random boot0: error) and started fresh with High Sierra. Everything is working great but my old Sil 3124 SATA PCI card that I used to plug in 4 more internal drives for media is no longer being recognized, and I can't for the life of me figure out how I got Mavericks to recognize it in the first place - I vaguely recall it involved downloading a driver from somewhere sketchy.

Any recommendations on a driver? Or even a replacement card? I'm out of PCI-E slots and can't find a HighPoint Rocket card that is PCI for the use I'm looking for. I guess I could get a PCI-E to PCI conversion card as well, I've just found the more hardware you start piling on, the unhappier your hackintosh gets :).

Thanks in advance!