Hey Tom,
I'm not trying to discourage your engine building but for safety and engine longevity reasons you might want to re-think getting a junkyard harmonic balancer.
Since you live in a very cold winter climate, and the last time GM used 292s as stock engines in their vehicles was 15 years ago, I'd say chances are good that the rubber ring on any damper you find has probably deteriorated to a point where it could be unsafe to run. A damaged or dry rotted damper ring could cause balancer separation, which could be disastrous for your engine if you're driving down the road while it happens.
The balancer I showed you from Ebay is only $45.00USD and is brand new. If you go to a salvage yard, you'll pay at
least half that much, if not more. And if you get it for less you'll probably have to pull it yourself.
So even if you don't buy the one from Ebay, at least get a rebuild one from Damper Doctor. They do good work.
-magic mike-
