It seems that these McCormick -Deering binders had a type 'D" (for Deering) or a type 'M' (McCormick)binding attachment, and the type 'D' had the twine box up front.
I thought for a start this was just in Canada, but when I got a manual from IH, this is how it shows it.
I purchased mine from NYP Corporation, and although it was in smaller balls than originally, (5 lbs per ball) it was lovely stuff and very high quality.
I thought getting good twine might be hard, but this stuff is all you could ask for.
Living up in Canada made shipping expensive. (Got a bale of 10 balls) but I only used a couple of balls so will last a while.
Here is a pic. of the crop it cut, if it comes out this time!!