I had a similar problem.... valve failed so had to replace
the cooktop in my 1300.
It is Atwood Wedgewood 56494 DV-20Scosting about $100
seven years ago... Looks like they are up to about $120>$140....
My installation required aluminum angle trim to make up for
the new unit being slightly smaller than the original.
Also installed was a little battery
powered igniter / photo,
big black button lower left. The toggle switch is to remotely
turn on a 600W inverter for the coffee grinder and juicer, etc.