Here's how the weights compare between the 3 motors I weighed. Strictly for reference. The sbc is a Dart-IE block with raised runner Brodix 18° heads and aluminum pan. The 496 is a production 2-bolt block with 781 ovals and Milodon steel pan, and the 548 is a GM Gen-4 block with Dart-IE heads and Moroso steel pan. All were measured dry. The 496 had an empty oil filter and flexplate mounted, the other 2 did not.
Regarding bbc vs sbc weights. I can't really say what a different combo would weigh. I just put these out there for folks to see. Some things to keep in mind are the 548's block is a 4bolt Bowtie block that is likely heavier than a production 2bolt block, the Dart-IE heads likely weigh more than the GM 781's. That's where the weight difference is between the 548 and 496 (most of it anyhow). On the 440sbc, the Dart-IE block is a heavy piece especially compared to a production Gen-1 block. The heads are raised runner units that will weigh more than a typical 23° alum head, along with the intake being heavier. I would speculate that a typical production block 406 with Al heads would weigh-in ~40-50lbs lighter than this 440.
nashville beth, if you make an offer that's accepted, ping me, I think I'd like to have one of those as well. I ship a good bit of stuff overseas, sure would help to be in the ballpark on weights. Past sales are for listing price, I guess nobody made a decent offer.