Looks like a very limited different lop options are a reality - and the pad to reach the 15” you seek DOES EXIST
- but the real challenge may lay in finding them in stock: Benelli Ethos 12ga. Recoil Pad 15" LOP
(MidWest GunWorks are great to deal with and I would still use any “Notify Me When Back In Stock” option available, if they offer it)
Im not sure if entering the item / product code (or upc #) for parts into the search function at search engines like gun.deals.com or Wikiarms.com may work as well as it does for guns and magazines but, I will try …
Turns out ^that^ search does work and I’d activate the “Notify Me” at this vendor as well (I’ve done business with Impact, they are legit):
Benelli Ethos 12ga. Recoil Pad 15" LOP. Benelli 80193. Benelli Ethos 12 Gauge Recoil Pad 15" LOP. This is a Benelli factory original replacement part. The installation of this recoil pad on your Benelli Ethos will increase the length of pull to 15".
Id also be inclined to call Benelli and ask them what different lop pads have been made and what the actual upc code is for each. That info will make searching for one a lot easier.
Owning several Benellis I’d also inquire if there is any possibility that a recoil pad from another gun in the Benelli line (a long one when it comes to semi-autos) might fit your gun.