Removing paint overspray from washer bottle.

[In The Ten Ring]

My truck's PO had a friend paint the truck and "taping off" wasn't something he had heard about.

My windshield washer pump is a mix of the colors black and ochre.....would paint remover get that off without harming the plastic?

Also, where is a good place to get replacement rubber hose for the squirter lines?

Thanks!