Chaz, it's been about 5 years since I've been to the shore. I actually used to go to ocean grove quite a bit because I like the boardwalk there, but only heard about the sister shop last year. I'm not sure which of the family members run it. Michele might have mentioned her father, but I'm not sure if he's still in the picture. I think I asked her three times if she was sure the workflow and ingredients were the same and she assured me they were.
The next time I go to the shore, I plan on making a trip, but that could be a while.
I googled 'metal Toms River' and came up with these
Laursen Sheet Metal
69 Flint Road, Toms River, NJ
Pinnacle Glass & Metal
1820 Route 9 # 1, Toms River, NJ
Park Steel & Iron Co
18 Irons Street, Toms River, NJ
Industrial Metal Recycling Inc
PO Box 1631, Toms River, NJ
Toms River Sheet Metal Co
Toms River, NJ
E P Homiek Sheet Metal
1352 River Avenue, Lakewood Township, NJ
Halo Sheet Metal Inc
140 Lehigh Avenue, Lakewood Township, NJ
Lakeside Sheet Metal
915 Alpine Street, Forked River, NJ
(609) 693-7792 · lakesideheatingac.com
Arnold Steel Co Inc
79 Randolph Road, Howell, NJ
(732) 363-1079 · arnoldsteel.com
I have no idea if these places sell to the public or not, but I would make some calls. I didn't google scrap or junk- junkyard plate is a bit controversial here. If I were shopping for plate, that's where I'd go, but others might have safety concerns regarding what materials the metal might have previously been exposed to.
You want the biggest square plate your oven can handle- touching the back wall and almost touching the door. Measure carefully to make sure the door will close.