What would be the correct oil pan on a 1969 L72? Did all the big block's have the same oil pan? Anyone have picutures?

I don't have pics, but the Camaro pan is the same for all 69 bb. I don't know what other chevies interchange, other than Nova for sure. Not sure about Impala and Chevelle.

Would they all have the windage tray/baffle or just certain engines?

L72/L78 has the double layered baffle. Not sure if lower HP b/b had the same baffles.

BTW the baffles interfere with a windage tray, so you can't use both. You may be able to dent the baffles or cut holes in them to clear the windage tray bolts. The factory did not use the windage tray.