Can someone tell me where I can get a transmission schroud for a 1975 olds 350 v8 rocket?

Do you mean the torque converter inspection cover?

Scrap yard, or possibly a transmission shop.

They would need to know the model of transmission first, likely a THM 350, (or if its a full size car, like an Olds Ninety-Eight, a THM 400)

However, the cover is not necessary. A couple of my cars have not had them for years and function well.

Yes, I mean the torque converter inspection cover. Is there any problem with that gear being exposed to the elements?

Road hazards are the pitfall. A rock that could otherwise be deflected, can bend the flexplate.
The same part number for the Olds fits the Pontiacs of the era.