I have a Motorola databook from 1972 with the flip chip datasheets in it, along with an old Nat Semi databook from the same time with a whole lot of chip die shots for hybrid circuits in it. Scanned, but the PDF's are close to 30M each, and my web host will kill me if I link them public.
The TO92 LED's I remember from AM International copiers from the early 1980's ( the small cheap 300kg units that would easily do 40 million copies before you replaced them with another) used with a matching TO92 phototransistor used as paper path sensors, mechanism position sensors and pretty much any application where you would use a low operation force microswitch.
The plus indicator is actually a filament display, you run it off 5V direct from logic. Very nice and very reliable, though I really hated changing those on aircraft equipment because of the wiring loom needing to be cut to get it out then relaced to fit the board back. They were rated for a 100 000 hour operational lifetime, really only failing from vibration but if you have a line of 30 40 year old ones that lifetime is getting pretty close to monthly. they were available NOS from the stores, with 30cm PTFE24 AWG wire leads.
Copper price I can agree on, I get good money for old copper cable at the scrappie, even more ( like $5 per kilo) for bright copper. You can see why it gets stolen.
Drager sensor does Oxygen, CO, CO2, Methane and SO2 detection, and is there to warn if you are in danger. Sort of an electronic canary, just needs electricity instead of birdseed. The oxygen sensors are scary expensive, and have a lifetime of around 6 months after installing, even if not used. Shelf life of around 2 years as well. I used to use them in FMCG packaging, and the cost for them was really painful, even if calibration was very easy by just adjusting the meter to read 20.5% in fresh open air and then checking it was under 3% in a flooded N2 bag ( 3% was the best the nitrogen generator would give at low flow, if you ran at full it would be 5% of O2 in the N2 output, good enough to give a boost in product lifetime without needing preservatives, and a shed load cheaper than having a contract with Afrox or Air Liquide ( and the cost of the generator was the same as a 2 month period of gas delivery) only needing oil free dry compressed air and a regular diet of 0.2 micron filter packs used 2 in series along with an upstream 5 micron oil coalescing filter. waste gas was around 30% oxygen, was looking at a fish tank but just vented in via a silencer. The other sensors are likely either heated pellet or safety fine catalysing gas sensors, operating by heating up a bead in a fine double mesh housing and detecting either a temp rise or fall depending on the gas concentration.