Im assuming it looks something like this?

Thanks a lot for the advice about the exclamation mark.

On machines without the specific key, the exclamation mark was often made simply by holding down the space bar and typing the apostrophe and the full stop one after the other.  Less finger work is required with this method, as, on suitable machines, one character may immediately be typed on top of the previous one this way.  Try it on your machine; some do and some don't!

One my Greek typeface machine, several of the apparently missing characters are easily fabricated like this, and that was the intention of the manufacturer.

Additionally, the compound exclamation mark by the above method will be half a space to the right in the text - which helps the appearance IMO, but one can backspace to avoid this if preferred.
Remember, as with all punctuation, it was often recommended that the key be hit somewhat more lightly than normal.