Mountain Equipment Co-op is great for filtration systems. If you are an avid backcountry camper, then this one is definitely budget friendly and so so so easy to use: https://www.mec.ca/en/product/5035-528/GravityWorks-4-0L-Filter-System.
There are many good options for backcountry water filters. The most popular one is the gravity type filters that people setup on their campsite and the water continues to filter down into a fresh container. But the gravity filters are expensive.
If you are looking for budget option, the most popular one is lifestraw.
I use a few different types of filtration systems depending on the trip. For backcountry and portage trips I like the Xstream straw with hand pump. I can tie the straw to my canoe yoke and just drop the filter in the lake at any time and drink. It’s a great product and cost about $75.00 canadian. For backcountry trips that aren’t serious portaging trips I bring the Katadyn Gravity 10L filter. This is also a great product and requires little work, You fill the bag with water, roll the top and clip it and hang it up. Whenever you want water, you just take the hose down, undo the clip and clip the hose to your water bottle/cup/etc. You need to clean the filter regularly to keep the water flowing quickly but otherwise requires little work or maintenance. You can pick up different sizes of this filter and the pricing runs about $100-$120 depending on the size. They do sell these at some Canadian Tire stores as well and have seen it go on sale for as low as $60.00. The other option I use for water filtration is Purinize drops. These are chemical drops you put into water, you can use water from almost anywhere, even a swamp and use the suggested amount of drops, wait an hour and drink the water. The water actually tastes like water and the drops can be purchased at Purinize online for as little as $15.95 for a 2oz bottle. I believe this would be the most economical way to create drinking water out in the backcountry. Hope this helps. Camper Christina
Check out this post, it has got some great suggestions.