I have found quite a few online but I am not sure that they will work.
Chowder is very popular in our house but due to the fact that I am feeding 7, it isnt a cheap meal, so I dont want to waste fish in something that isnt very nice. We dont eat meat or fish every night, so when we do I make sure that it is a really nice meal that everyone can eat, frankly I cant afford to waste anything.
I dont think that cauliflower will work as a substitute for spuds that some recommend, its got too strong a flavour.
Celery stalks with a thick spread of pate Little gem lettuce This bread if you must have bread - www.thelondoner.me/2014/03/mums-low-carb-bread.html It keeps a week in the fridge in a sealed container, you can toast it, and I find even non-low-carbers will eat it.
Melba toast is not ok on boot camp. There's a spreadsheet with the rules pinned to the top of the weekly chat post. You need to cut out all bread. Lowering your carbs is a good idea but if you want to follow boot camp then no bread.
As for chowder cauliflower does make a good sub, it's amazing how you tastes change when you cut carbs. Personally I really didn't like the stuff before but now it's one of my favourites and very versatile. I wouldn't say it's the same as a potato chowder, but I like it. I'd probably reccomend you make a small batch to try and see if you like it.