Hi t,
This company is still in business, see:
http://www.foxboro.com/m&i/controllers_recorders/recorders.htm
for a modern version. I have no idea of the time period for that piece, but they might be able to answer that.
I would guess that your recorder is not RR specific, but this type of instrument would be necessary to record temperature performance in a reefer, like you said, and it surely would not be incorrect to refer to this as a reefer recorder.
I also guess?? that the hole is a keyhole for the clock winding key, which would prolly be a square (inside) key which you could find at a clock shop.
I'd bet that this instrument could be made to work
with a little effort if the clock is not totally rusted up inside. The paper charts are still available, depending on the specific size.