Dumbo was re-released in the UK on the 13th August 1972, & in France on the 9th December 1970. Clearly release in France was too early to catalyse this set, so on this occasion it seems the idea would be more likely to have originated with Waddington's rather than with Comano.
The Comano 1972 catalogue lists nine Calcoramas, four of which (shown here) have Panorama connections. "Dumbo Circus" is at the top of this scan. You can see that the three-foot wide background is only slightly similar to the much smaller Dumbo Panorama background.
The Dumbo Circus Panorama was announced as new in the 1973 Waddington's House of Games trade catalogue.
The much later Mako Calcoramas abandoned the box in favour of a more "Storytime Doodles" approach; here's the background from that version, which is essentially the same background but drastically reduced.
Wait; cancel that. This isn't the background from "Dumbo Circus" Calcorama; it's from "Bozo the Clown". Interesting… what were they thinking?
Anyway, here is the first sheet of transfers, which would apply to both the Waddington's Panorama & the Mako Cacorama. If only we had sheet two as well (of four sheets in all), we could show you the full set of Panorama transfers — albeit with the wrong text on the sheets!
Well, I CAN show you the other three sheets, as it happens — just not in much detail. The original Mako Calco sheets would be numbered 4407; these (& the one above) are the later-but-identical 441-7 sheets.
And just in case you were suddenly curious to see "Bozo le Clown"… (along with the back of the Babar Calcorama, to confuse you):
