Can’t resist a cue/prompt like that ! I’ve seen these tanks with lever action taps with the small-diameter delivery holes, as described, but the more usual fitting was the Enots dial-faced adjustable drippers, which are MUCH better, being infinitely adjustable to suit the viscosity of the oil, which of course varies with the air temperature, and the grade of oil in the tank. It is important to drip the oil onto the inside of the chain run, so that it centrifuges out thru’ the sideplates and rollers. In road use you only need 3 or 4 drips per minute. Otherwise it can all get very messy…..
Personally I fit the tanks and pipework for the sake of history and originality, but use a non-fling aerosol chain oil before each run.
By strange coincidence, I bought a chain-oiler tank complete with Enots drippers, only two days ago, and it is in the post as I type this reply. Sorry, they will NOT be for sale !