I would suggest just going to the junkyard. Get one out of an XC90, a lot of those have trailer wiring and the plug is the same. The guy charged me $2 for it and I soldered it to my 7pin in my V70. I also picked up a Hopkins Insight brake controller and mounted it in the dash. (these allow you to hid the brain box in the dash) They are still $99 at Rural king. It was a pain to put all that in as I had to take the interior out to run the wires in the Positive trough to the back of the car. Put an additional fuse in the rear fuse bus next to the battery. I had to run the brake control cable to the back anyway, so I just added the power and brake light indicator wire as well. The only thing is that you have to add a diode on the brake light indicator circuit because the car grounds the brake lights when the lights are off. The controller expects an open.
Oh, and if you get a used harness, it may not have a pin added for always power/reverse/fog light. You have to pick one because the 7 pin doesn't have enough terminals. The correct pin size is in a plug behind the left rear speaker cover in a V70. Take one of the large pins out of that plug and it will work for the small pins in the trailer harness. You can pop the red part off of the plug with a small screw driver or your fingers, them pop the pin out from the front of the plug with a small screw driver. Ford Escorts (I think late 90's or early 2000's) used diodes in their fuse boxes. You just cut off a little tab on the diode and it will fit in a regular fuse holder. Easy to wire inline for the brake signal light.