I don't know exactly what the geometry looks like here but you may be able to find larger bearings that will fit the ID of your existing hub and the 1.25 OD of the spindle that you can find.
Ended up using the one that fit the larger bearing. ( Industrial spindle)The vertical shaft was longer. I had to weld the control arm to it as keyway on opposite side of longer shaft and had nothing for a spacer . Think the one I replaced was a modified original. At least everything is we working well. Also glad I have a timken reference book
Yeah, there's at least 3 front axle setups on the 4000 tractors... one's like the 3000's, one bigger with shorter spindles, then the high crop setup with tall spindles like a 5000 or bigger...