Yes I know the one, it has a push button on the top to test the light? If so MK2 Fiestas have the same, and so you could also use one of these, which again are hard to come by. Probably other Fords do as well.

I can keep an eye out for you if you like? Unfortunatly I have access to plenty of others but they have the big reservoir (I can check next time I see them)

Martin