When we're on the boat, I do try to keep a fairly well stocked larder cupboard - we do have a fridge, but there isn't always a shop to buy fresh stuff. So the answer is tinned food, mostly.
And, hmm, don't peperami need to go in the fridge?
Eggs of course, tinned frankfurters and corned beef, as has been said. Look in the tinned meats section - there will undoubtedly be other things you can take along. Hardboil some eggs before you leave.
For veg - tinned spinach is very useful, also tinned green beans. Tinned ratatouille is incredibly useful, I've always got several cans of this in the cupboard. Don't forget mushrooms, you can get them in tins as well. Have a look in the tinned veg and see what is available. Also, sauerkraut - Sainsburys do one in a jar, in white wine which is really nice - be careful of the ones in vinegar as some of them have quite a bit of sugar added. Check the labels. Also pickled cucumbers are good - again watch out for added sugar.
Don't forget snacky things - porky scratchings and macadamia nuts are good. If you can find jerky or biltong that doesn't have sugar in it or MSG, then that's another idea.
Something else that occurs to me - shirataki noodles, also called
zero noodles. I have not tried these yet, but hear good reports of them. Most importantly for you, you don't need to keep them in the fridge.
Pesto in a jar - stir in pasta sauces in those little pots perhaps, check the carbs though - pasta sauces in a jar, again check the carbs, some of them are quite low, others are not ....
Tinned sardines with chilli - tinned mackerel in oil - sardines in tomato sauce.
Tinned ham.
Make sure you've got enough veg - it always seems to me that veg is what makes a meal.
I don't know if those longlife yogurts are available without being loaded with sugar - and I also have not sorted out anything out with regard to cheese.
Hope this helps a bit, anyway!