There is no need to buy any kit to fix this leak.
All you need to do is replace the o-ring on the shaft seal with a 3/4 X 15/16 X 3/32 (ID/OD/section) which you likely have on the shelf somewhere if you have a standard o-ring kit.
To get the steering wheel off use the method described by Ray66V - loosen the nut until it is flush with the shaft, brace your knees under the steering wheel and apply upward pressure, place a large brass drift on the nut/shaft and strike it with a hammer, two blows and the wheel will be off - no damage done.
Disconnect the pump - label the hoses
When you have the pump on your bench scribe the sections so you know how to line it all back up when assembling although it does not really matter as the pump is symmetrical just make sure you know which hole the bolt goes in and you can figure that out with the pump apart as it is the only dead hole.
Polish the rust off the shaft and lubricate so you do not damage the dust seal when removing the spool.
When the pump is disassembled remove the spool (part the steering wheel attached too) make sure both washers and the bearing come out as well (#7 page 4 in the PDF provided by Mac Clarke) and push the seal out (part 5) with your finger nail or really light pressure with a screwdriver (it was teal in colour on my pump)
Replace the o-ring with a 3/4X15/16X3/32 o-ring and reassemble
Done
Cost < $1
This is how I fixed mine
All you need to do is replace the o-ring on the shaft seal with a 3/4 X 15/16 X 3/32 (ID/OD/section) which you likely have on the shelf somewhere if you have a standard o-ring kit.
To get the steering wheel off use the method described by Ray66V - loosen the nut until it is flush with the shaft, brace your knees under the steering wheel and apply upward pressure, place a large brass drift on the nut/shaft and strike it with a hammer, two blows and the wheel will be off - no damage done.
Disconnect the pump - label the hoses
When you have the pump on your bench scribe the sections so you know how to line it all back up when assembling although it does not really matter as the pump is symmetrical just make sure you know which hole the bolt goes in and you can figure that out with the pump apart as it is the only dead hole.
Polish the rust off the shaft and lubricate so you do not damage the dust seal when removing the spool.
When the pump is disassembled remove the spool (part the steering wheel attached too) make sure both washers and the bearing come out as well (#7 page 4 in the PDF provided by Mac Clarke) and push the seal out (part 5) with your finger nail or really light pressure with a screwdriver (it was teal in colour on my pump)
Replace the o-ring with a 3/4X15/16X3/32 o-ring and reassemble
Done
Cost < $1
This is how I fixed mine