Only the co-op or asda wholemeal ones qualify as a HEb, no others I am afraid. Slimming World carefully select all healthy extras by a variety of factors. There is no way of substituting the list with our own choices (if only eh??? lol)
Other wholemeal brands you will find most likely have oil in them or are above the weight of a healthy extra etc.
It really depends on whether you want to be 100% on plan.