J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment tuff luff or harken

You should be ok if the groove is the same.

Class rules permit the foil to be up to 31 mm deep (1.22"):
5.8.1.2 Jib luff groove systems other than that which is provided standard shall not have a fore-and-aft dimension exceeding 31 mm.

Here is a Harken spec sheet link