The part number of the impeller you need is 1A8737, email Florin Tractor Parts in California, they might have one, though it's a long shot, you are more likely to get a complete used pump off someone, there are quite a few 22's in Oz, the bearings and grease seal are still available from Cat, the packings you can make with graphite impregnated pump rope.
I'll PM you a email address for Florin
regards
Mike
I have an impeller still on the shaft. Shaft is no good. You drill out the pin. . $25 plus shipping from CA. - Wally