These are available new from various sources though since you are in California I suggest you have a look at the sixties buick V6 and V8 engines as they use the same front cover and pumps on some models. other than that you might try All British Cars in Burnaby, Vancouver Canada. The Canadian Rover Car club (RSTCA) also has a list of parts companies that could supply. Note that the pumps are different to SD1 pumps though some have the better impellor fitted with curved vanes, which improves flow and reduces effort. Finally they can be rebuilt, the seal is a standard one, but when pulling the impellor you have to heat the unit up first (I use cooking oil as it doesn't stink) and ensure you pull from as close to the inside as possible so as not to break it. they can pe pressed back cold but I prefer hot impellor cold shaft as it maintains the locking pressure between shaft and hole.