Pre 1970 timing cover???
I think '69s, maybe LATE '68s, were the only ones to have a cast-in timing scale. Most '68s and everything before that were bare and used a bolt-on timing tab.
I don't know of anyone reproducing the early timing cover, with or without the timing marks.
Don't worry about it though, if you need an early one, just use the late one with a bolt-on tab. The driver's side marks will be hidden by the early water pump inlet anyway. The TCs are the same other than the timing marks, or lack thereof.
I think '69s, maybe LATE '68s, were the only ones to have a cast-in timing scale. Most '68s and everything before that were bare and used a bolt-on timing tab.
I don't know of anyone reproducing the early timing cover, with or without the timing marks.
Don't worry about it though, if you need an early one, just use the late one with a bolt-on tab. The driver's side marks will be hidden by the early water pump inlet anyway. The TCs are the same other than the timing marks, or lack thereof.