I bought this '60s made in Japan Gold Foil on eBay "as-is" with the intent to repair it. It had no output and showed no resistance on the meter so I took the cover off by removing the phillips head screws on top.
Next I removed the magnets which are simply held in place by their own magnetism on either side of the coil. They were installed with South polarity facing up. As I was inspecting the coil, I removed some tape and noticed the tiny 44 gauge coil wire had become detached from the white lead wire. I resoldered and checked the resistance, it was now showing 5.3K.
This might seem like a low resistance for a single coil, but don't be fooled! The low resistance makes these nice and clear while the powerful magnets and the squatty coil make it sound full and fat. I have repaired another Teisco Gold Foil that was around 6.3K and I have seen DeArmond pickups showing upwards of 10K, so there is quite a variance in specs of what is called a "Gold Foil". I based my own Humbucker-size Gold Foil pickups on vintage pickups I see come into the shop.
When dealing with classic pickups like this, it is always better to use the original coil if possible for the most authentic tone. The most common cause of dead pickups I see is sweat or moisture corroding the coils. Usually there is no other way to repair a corroded coil than to rewind it, which I will do with vintage-spec wire to the appropriate number of turns. Rewinds usually cost about $50 per coil.
With this pickup I will probably wax pot it so that it will be less microphonic and install in a Telecaster. Here is a quick video I made of the pickup in my tester guitar: