Here's an Ebay link which indicates that you have a number of donor vehicles to choose from (including mine, but you can't have that one). And with the prices they're getting for this thing, I'd agree with trying to pull one from a yard.
I don't think it's dumb at all to use a torque wrench for gaskets like this, particularly for someone who doesn't do much of this stuff. 'Feel' is something that's acquired over time - no one is born having it. I suspect that far more mistakes have been made by people working by feel, than by those using mis-calibrated/broken torque wrenches, or not understanding their operation.
IMO your only mistake was not doing a 'reality check' on the torque wrench before actually using it on the job. I do this before starting any sensitive job - just a quick test on something like a wheel lug, just to make sure the tool is in the right ballpark. So for 80" lbs, the tool should 'click' with almost no force applied (or move easily on the dial if a beam type). Good luck finding a new VC, without needing to take out a second mortgage.
2011 3i 2.0 A/T 130K miles (daughter's ride which I maintain)