Possibly, though, on the full-size image, there's no yellow on the top of the rail on the far side, and there doesn't seem to be anything at the other end, though the rust just could be from the bolted-up face?
It might depend on the 'style' that you want - you may be able to use one that is intended to be a rail tunnel - or you might be able to use a bridge, and saw it lengthways - or possibly make what you really want from some Will's sheet?
Vulcans, Valiants and Victors were painted white in the early days, as 'flash-protection' from the thermonuclear explosions they might have ended up delivering - so, if you happen to be flying in a white plane when Trump or Putin finally get fed up, you have a slightly higher chance of surviving for a few seconds longer.
8mm square? The stuff used as expansion strips for laminate flooring tend to be a little bit bigger.
But, it's probably worth asking, if you have a local installer..
https://hardwoodfloors.uk.com/strips-skirting/cork-expansion-strip
For those interested, the conversion kit is around $700 - $900.
Though a DIY version can be achieved for a lot less, they say...
http://thequirkyglobe.blogspot.com/2011/06/old-fashioned-typewriter-connects-to-pc.html
You can just make out the conveyor in the undated photo at the bottom here - https://jetstream.gsi.ie/iwdds/delivery/GSI_Transfer/Geoheritage/LS019_Lisduff_Quarry.pdf