There's an electrical parts house called AuVeCo that may have a local shop near you; if not, find them online. They have every kind of auto connector imaginable. As to your heater, if you haven't damaged the new one, take it back for a refund. You do not need it, and as noted above, they're prone to failure and when they do they blow #22 (IIRC) maxifuse and cut the power to the PCM (the brain) and you're dead at the side of the road. If your connector isn't leaking fuel, then snip the wire, cap the ends, and the hell with it. I live in NW Ohio; it gets plenty cold here and I've never had an issue as a result of removing the fuel heater element about eight years ago.
If you are refering to the connector on the fuel bowl itself that the fuel heater plugs into on the inside and the harness plugs into on the outside (I'll call it the fuel heater feedthrough), note that it is not just a direct passthrough. It does have some sort of "thermostat" function. The part number for it is F4TZ-9J294-A. Tousley Ford Parts online should have it for about $40.
I would just leave it disconnected.....If you use anti-gel additives and make sure fuel filter is good , you don't need it...It gets -25 C here in winter and I have never had a problem....I use Power Service religously however ...( white in winter and Grey in Summer )
Patrick - Are you sure of the thermostat function of the fuel heater? I recall reading here that the three 'solder' joints (the ones that fail and allow the element to short out by touching the canister) are "thermistors" and thus transmit some sort of changed electrical value to (I'm guessing) the PCM, depending on temperature, but I don't recall ever reading how the PCM uses this or how my engine's performance might be affected by eliminating the heater from the info stream. Can you shed any light on this?
I just remember someone posting (I don't remember what PSD forum it was) that they took some measurements of the part and it was not a "direct" feedthrough and it was more like a thermistor. The PCM does not monitor any parameters associated with the fuel heater circuit (the circuit is simply powered off the same power feed used for one of the PCM feeds). Eliminating the fuel heater will not have any effect on performance (mine has been disconnected for a few years now). Cheers!