Your motor should be repairable, infact the oldest daihatsu parts catalogs had repair kit for the wiper motor for g10 and g11 models. G100 had modular units.
Its a very simple motor with 2 carbon brushes and a park switch on the transmission. Find an oldschool person who can rebuild starter motors (as in rewind the armature too) it would be a piece of cake for them.
Hint: truck adda places have such guys