CT-### in connection with Caithness weights usually refers to the numbers Colin Terris has used in his Charlton catalogue, i.e. they don't mean that Colin Terris was the designer.
CT-184 is "Nativity, Style 1" by Helen MacDonald - something completely different. Most likely boxes were mixed up at some stage (or the number means something completely different). This weight could be the one I mentioned above, however: that the eagle is catching a fish may just not show up on the images I have copied off ebay; of the two I copied, one seems to have been unsigned, the other marked as second (CIIG), which could also mean it was a trial piece (this topic has been discussed here previously). ... If your weight is actually signed Caithness, I would very much appreciate if you could provide images (several views, including the signed base) for ScotlandsGlass.
With Osprey also the box does not (originally) belong to the paperweight: Osprey is a spherical weight with oblique front facet - completely different from Eagle Dome, the weight starting this discussion. No specific designer is listed for Eagle Dome - just Caithness Design Studio. First issued in 1976 it was produced over many years - so some variation in the dome shape wouldn't surprise me at all.