That's a real beauty! I don't have this model(yet!) but I do have a similar Brother straight stitch machine. An HA1 manual might work, I'm not sure if this one has the same type of upper tension assembly or the one that's just a hair different in the threading of the upper tension. But it looks like you got that covered. Mickey pretty much nailed it on the oiling. I don't think I can add anything useful.
Cari