Buy just the bag and find a medical supply house in your area. The supplies are pretty cost effective and can be bought separately. Look in the industrial parks in the cities around you or that you live in. There will be medical supply houses that stock first aid kits and supplies as well as hospital supplies and such. Get a list of goods and stock everything you can. They may also be designated as rescue supply or safety supply. Avoid drug stores as the costs are exorbitant..

If you can't manage all the goods buy PPE (gloves especially), trauma bandages, chest seals, tourniquets, tape (hockey tape works surprisingly well for a lot of things) and a pair good heavy medical shears. Stock as many as you can manage. Those will be the most used items.

Here is a list for a good basic Field kit you can follow. Put it in a pouch that can attach easily to a belt or a pack and be accessible always.

PPE (gloves, mask, eye protection)

Small pocket mask, NPA, OPA

Trauma scissors

Quick clot

1 or 2 tourniquets (SWAT-T, CAT)

Chest decompression kit

2-3 trauma dressings (Israeli type)

4-6 hemostatic dressings

2-3 open chest seal (Bolin, Hyfin, Asherman)

4 roller gauze, compression bandages

1 heavy duty 2" tape (e.g. NARP Gecko tape)

1 personal care kit (PCK) that includes personal medications, sunscreen, insect repellant, and/or contact lens supplies

Edit: here is an online supply house from Canada that has many items to choose from. Canadian made is going to be hard but I'm sure if you contact them they will do their best to help you out.

https://canadiansafetysupplies.com/

And sands has been a Canadian supply house for years. I have ordered from here quite a bit over the years.

https://sands.ca/

They have this very basic premade kit as well...

https://sands.ca/products/blood-stop-kit-1199468348-html?_pos=12&_sid=f0108cf11&_ss=r