For a camping grill I have an old BBQ one that I found in a skip. Just the grill part cut in half ... pretty robust ... balances on a few rocks just right. Not big ... 15", 16" long and semicircular; about enough for a fish or a couple of burgers
You could look at the purpose-made ones like the Coghlans foldable, or the ones made by Grilliput ... Personally, I sneer, but a friend much more capable than I swears by his and has twice gone to great lengths to retrieve if from distant sites where it accidentally got left at packing up time
They don't warp if you grill with embers taken aside from the fire - don't want to be using them as a stand to boil water over the open fire itself. They'll look like Heinz spaghetti in no time.
Oh, and a bag for it will be very handy. Dirtiest thing in the world, a recently used grill is, and a faff to clean when you're out.
There is also here, of course
...
https://snowpeak.com/collections/cooking
One other thing you might consider is buying a Weber Q grill for the garden/carcamping (there is a range of them) and just take the grill plate with you if you are going to be using a fire. (Might be just a bit big for packing, though. Depends on how you roll)