Can I order a 1000BASE-LX transceiver from any source and it will be compatible with all others 1000BASE-LX ?
Would a link with a Juniper 1000BASE-LX and a TrendNet 1000BASE-LX transceiver work?
While this is true on the fiber side of the system, and SHOULD be true on the thing with the transceiver socket (SFP, typically, for current Gigabit stuff) it is evidently not always true for certain annoying manufacturers that like to lock you into their house-brand transceivers at far above the cost of standard/generic/standards-compliant transceivers.
One of many reasons I avoid certain brands by default.
Unless you want to connect one SMode transceiver with a MMode transceiver, you will get your link UP, because they are standars of the market, and only can be negative the transmision distance from one to other, or wavelength mistmatch(850, 1310 or 1550 nm) . Here, on Wikipedia: https://es.wikipedia.org/wiki/Gigabit_Ethernet, you can find the transmission distance of each one.
In other words, if you are on the working range, all the tranceiver will work normally.