I found a Lucas part number on the rubber lower sleeve. Lucas calls it a bushing, sometimes abbreviating it as bush, and refers to it as a rear bushing.
The part number is 744983. It seems these were used on some Jags and Lotuses (Loti?). However, after looking at photos of the part online it looks like the ones on my car were modified either at the DeTomaso factory or by a previous owner to both change the angle and make them shorter. The flat surface, perpendicular to the cylinder was not cut. That is where the part number is. The angled surface was cut - perhaps by a bandsaw.
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