I did a similar thing. I managed to break the mirror itself off of the housing (mirror is fine, but the plastic swivel is broken). I have heated, dimming, turns signal, memory mirrors, so I could not find a replacement on
ebay. I ended up shelling out $890 (installed) for a new one because they only sell whole mirror assemblies.
Before I spent the money, I tried to repair the damage as the mirror itself was perfectly fine, but only the plastic housing that holds the power pivot mechanism was broken. I figure it is a $2 piece of plastic. You can remove your mirror by simply pushing straight up on the mirror to unhook it from the holder (assuming all Tundra mirrors attach the same way). The whole assembly is apparently removed with only a few bolts inside the door. I tried gluing the parts on my mirror back together with no luck. 3 diffrent types of epoxy refused to stick to the type of plastic they make the mirror assemblies out of.
I feel so bad spending $900 to fix something that I could do myself with a $2 part. Oh Well.