Subscribed, I love these old Metros.
For what it's worth, you can get a RockAuto alternator for $80 new, or a remanufactured one for $67 after a $40 core charge (might or might not be worth it after shipping).
1989 GEO METRO 993cc L3 Alternator / Generator | RockAuto
Might be able to do better on eBay, but you can never be sure of what you're getting.