I've had nothing but trouble doing that over a period of years. The individual market for them is catch and catch-can it seems. I've had very good luck with Ali and ebay seller conhismotor ove repeat buys. I've had decent luck with electrobikeworld dotcom with fat G060 motors, front and rear. I THINK they sell the 1000w G062. But I believe you can forget about a 1000w front version unless you get lucky. Front motor availability is really difficult in terms of reliability. I looked for probably a couple of years for a front 750w G060 before I finally found them on sale at EBW. No guarantee they will stay available.
Speaking of which, Bafang has changed the plugs on their motors which means the motor plugs no longer interface with controllers made by a third party - which was the reason Bafang did it. So be careful which plug version you buy. EBW sells adapters but they are the only ones I have seen who have them... and of course they want ransom for the things.
There is a brand new 2-speed Bafang motor. 1000w and 95 Nm. Should be a unicorn for I am guessing about two years but if you can find one its definitely worth a look. Its designed for a single sprocket, which makes some sense since a hub motor doesn't care about gears, anyway. 2nd gear hits around 16 mph and it should be good to 30 mph. It is the G06A2, or H720.
Bafang description
bafang-e.com