We have several size options on the way right now. We are going to look at all of them and figure out which fits the application best and send the others back.
It will not be factory.
@ 801mbz, thanks for the offer, but we already had the other options on the way.
BTW, the DC motor I listed early in this thread will not work. The shaft diameter is too small.

__________________
1985 300 TD 448K
1984 300 TD 278K

1983 240D euro 240k
1994 f-250 idi turbo 330K
1986 f-350 IDI
1987 F-350 IDI

1985 JD 1050 4wd
1965 IH 3660

We ended up installing this fan.
http://https://www.amazon.com/BETTERCLOUD-Universal-Electric-Radiator-Cooling/dp/B00MJO4EC0/ref=sr_1_1?dchild=1&keywords=7+inch+radiator+cooling+fan&qid=1624290451&sr=8-1
We cut the original shroud and the new fan fit perfectly inside allowing us to reuse the original mounting screws and gaskets.

Attached Thumbnails

     

__________________
1985 300 TD 448K
1984 300 TD 278K

1983 240D euro 240k
1994 f-250 idi turbo 330K
1986 f-350 IDI
1987 F-350 IDI

1985 JD 1050 4wd
1965 IH 3660

Obviously its the wrong time of year to test it out, but it blows lots of air out the vents. Since the old fan was completely dead, we can't compare noise levels, but it sounds no louder than you would expect.

__________________
1985 300 TD 448K
1984 300 TD 278K

1983 240D euro 240k
1994 f-250 idi turbo 330K
1986 f-350 IDI
1987 F-350 IDI

1985 JD 1050 4wd
1965 IH 3660