Was the car purchase a private party or through auction? Your car must have been in very good condition to sell off that much stuff and get decent $$$. I'm glad your experience with the donor was a positive one, there are others in the forum who have not had this same experience and is something that many of us are trying to avoid to take a smaller hit to our budgets.
Just finding a SS/TC that can used as a donor - blown engine or not - is a real challenge; I'm in the middle of this challenge right now. TCs are coming up on occasion for sale, but are $5K to $7K in driveable condition - with 120,000+ miles - with potential resellable parts that are not beat to hell or a rust bucket. These cars are not worth cannibalizing from a $$$ standpoint in my opinion, since the parts used versus the parts resold will be on the far negative side of the value equation. Occasionally someone gets lucky and finds that good condition car for a reasonable price and can actually break even when all is said and done.
Insurance cars are filtering thru the auctions, but many are not worth purchasing with big hits on the front end that show visual damaged to many of the parts that are needed for the build or flood cars that look good but are iffy at best for the electronics and drivetrain internals. Avoiding certain areas of the country where rust grows on cars like leaves on trees is also a limiting factor - lived there in the past and know what problems are associated with trying to reuse these parts
.
The bottom line: the value of a car that will be used as a donor, that will not break the bank and meet the needs for the person doing the build, is a hit and miss proposition at best and luck plays a big part in finding that just right car to purchase. Good luck to all.