The NAMC’s “Catalog of all Series Matchbox Models” (
second edition - thanks for the copy, Dick!

) has 53-3A listed as having a blue interior. Houghton also has an unlisted model heading his listing as variation 53c-1, this time as Nick's code 1 but with a dark grey interior. I would suggest that both these models are pre-productions/interior colour tials, and analogous to the well-known violet-interiored version.
The AIM “1-75 Series Regular Wheels” catalogue (second printing, 1983) has no variations not already covered by Nick, and neither does Stannard.
U.K. Matchbox did not cover the model.