I would say yes seeing as they only state not for
Cupra R.
Also this is the arm part no. for 2004 Leon on Vagcat.com:
1J0407151C
track control arm / F 1M-3-055 800>>*
/ AHW,AXP,AEH, AKL,AZD,AGN, APG,AUQ,AQN, AQM,AGR,ALH, AHF,ASV,ARL, BCA,BCB
...which ties up with the replacement OE ref no. listed on vwspares.