I have an oil leak directly below the alternator where a wire connects to some sensor or something. I am wondering what this part is so I can find the right seal to replace

That would be the oil pressure switch, they do leak like that sometimes. There is no seal to replace, just replace the switch. You can get generic aftermarket switches, it's 1/8" bsp thread. Some thread sealant is needed.

Thanks I'll give that a try