Yep.....several out there. There exists one with the WSM brass called the 358 Grant. It's larger than my own but I went for simple and economical to create in a set up as well as "find" brass for.
Dave made the reamer for my smith from my brain "storm" (or flatulation).
THANKS DAVE!
Dont sell them too short (pun intended). ;D
Still working loads but mine is a ballistic twin to the 358 WSSM IMHO..just easier to form if the shooter isnt "anti - belt". Just ran a couple loads and 2500 fps with 225 grain noslers isnt a hard thing to get to. Need to pick up some "faster" powder for anything more or for lighter bullets but BETTING I can improve on that close to 100 fps if I push it.
For MY use , the above stats are more than "enough" for whitetail here in IN with equally more than adequate trajectory. There is a few out there faster, but this one is an easy one requiring no neck resizing, only a simple shorten and trim then check for any slight donut.
This round can be made from virtually any belted mag brass as long as you have a neck turning tool. I thought I had "issues" at first because Im too ignorant to realize that one DONT push the trim die all the way down for my round......and I did at first. :

(First wildcat)
The trim, FL, Neck and Seater are simply shortened Redding factory dies.
The 350JR is below next to the 350 RM parent round.
(Shortened 350 Rem Mag, no other changes BUT a slight straightening of the body taper and sharper shoulder could pick up a little....but I didnt personally see them worth the small gain, so I left it the same as the 350 RM, just shorter.)
NOT saying that this one of mine is any BETTER.....just one I did and like.
It's been FUN!
To my knowledge, mine and my buddies are the only two in existance but Ive got another 700 classic 350 RM going to the smith soon.
God Bless
Steve