You should google the casting number whenever someone shares it and makes a claim. 3969854 does show as 69-27 396 or 402.
As others have said, the accessory drive brackets could be worth more than the rest.
As a point of reference I have an ~80 454 for sale for $400 (on CL) no brackets but has the flexplate HEI and water pump (core). The current offer is $300.
BBC parts aren't all that popular since the LS got popular, but some of us like it...
