[FWB]

i have a fiat washer nozzle on my car, it has dual outlets, mounts in the center of the cowl, the orifices are angled to spray bothsides.

you can use a generic inline pump, there are a few out there to choose from and any reservoir will do, most wiper switches do have a wash option so it can be wired in without much fuss.

the Fiat nozzle is Fiat part number 4329692, i'm sure Moss motors can cross that to whatever part number it is now.
or just adapt something from some 70's era british car. MG, triumph, jag, go for a stroll in the local junkyard, you'll find something that strikes your fancy