I picked up an 84 Winnebago built on a G30. Live in the desert so not much need to turn in the wipers since I picked it up! Went to fill the washer fluid... no jug, no pump. The mount bracket is there along with a hose and 2 blade power connector. Picture attached.

having no luck finding a jug that fits an 84 g30 specifically. Anyone know the year range that this part was common on? Or where I might dig one up?

Missing washer jug and pump

 

I would recommend the junkyard . It should be the same for G10/G20/G30 within few years.

If not, there are aftermarket universal kits.

https://www.napaonline.com/en/p/BK_6651594

 

Junk yard. The washer res mount looks the same as my '93. Likely be able to use one from anything up to '95, maybe even newer. The pump should be available from the local parts store. I would suspect if the bottle is the same, the pump likely is too.