There may be a JST or AMP equivalent ( form, fit and function )but you will need the mating half housing and the 4 male crimps.
I did have a look for the Molex numbers this morning but as yet no success.
If I can find the Molex numbers I will try to find an alternative , and then get part numbers for the mating part.
When I did mine. ( Both the 1.9 and 2.8 ) I bought seat pads which came with all the wiring, so used the 4 way plug and sockets from that to make the connections