Be aware that slimming world are going to stop (if they haven't already) certifying butchers as syn free, because a) they can't guarantee that the butcher will continue to make their product syn free after certification and there are some unscrupulous sorts that claim to be syn free when they are not.
Reputable butchers who have been doing this a long time should still make their products as they have been because it makes good business sense to do so, but they won't be official any more...