Good to know!
I just found these...not vintage but possibly handy? It's a shirt pocket oiler made to look like a heavy duty ink pen.. The threaded front barrel comes off as a drip catcher...what I like is one press of the clicker button is supposed to dispense 1 drop per press..if the tiny plunger meters a single drop per press...and your finger is providing pump pressure...maybe it would pump Wilesco steam oil for sure? Not sure about the heavy grades...