AFIK the part is the same for both. GAP doesn't list part or model numbers, but the ball joint Techtonics Tuning sells fits all the models I've listed and doesn't specify the country of manufacture. This is the link to TT's page for reference.

Ball Joint '88-'92 Mk2, Corrado G60, Passat 16V, Mk3 2.0L [445 312] - $24.00 : Techtonics Tuning, Watercooled VW Performance Parts, Audi Performance Parts specializing in exhausts and camshafts