Nuts, seeds (watch the quantity and check the carb values) or something like Babybels or some cold chicken might not effect your bg levels, I find any snacks between meals causes a bg rise without insulin, but see how you get on as you may not find the same.
I like to nibble on Biltong. But make sure not to accidentally pick up the coated or treated ones as they can be a bit on the sugary side. But good old plain biltong is lovely.
I have found you can buy lots of 'protein bars' that are low carb, taste great and are fairly filling. Most notably Quest bars. If you google them you will see that they have between 3-5g of carbs per bar. Each bar is is a good size and filling, plus has lots of protein and they taste really good.
I like to nibble on Biltong. But make sure not to accidentally pick up the coated or treated ones as they can be a bit on the sugary side. But good old plain biltong is lovely.
Beef jerky is very good but too many proteins can have side effects plus they raise BG. Pemmican than is way better even if a bit labour intensive to prepare