I can't speak to what products are available in Canada, I'm afraid, but I have worked as a LARP weapon maker, both for a small but respected UK LARP weapon maker, and taken private commissions myself.
In the UK, the standard for most LARP weapons is: -
- Fibreglass or Carbon Fibre core
- LD45 "Plastazote" foam (a type of closed cell polyethylene foam).
- Liquid latex coloured with black acrylic paint as a base layer.
- Acrylic paints mixed with a small (5% ish) amount of latex to do the colours.
- Isoflex clear special roofing primer as a top "varnish" coat.*
- Silicone ("pure" silicone, the kind used for shining latex clothing) at the end to stop the incredibly sticky end product sticking to other weapons.
Some smaller makers have experimented with using FlexPaint, PlastiDip, and other similar products instead of the above, but in terms of durability the products I mention are more or less an industry standard.
As a general rule I would stay away from EVA foam precisely because it creases, dents, and tears so easily. I believe cosplayers restore their prop weapons with a hairdryer after events, but that doesn't seem practical for 26 weapons each performance.
Any liquid latex can work in a pinch. The stuff from Amazon will probably do. We do between 7 - 10 layers per weapon, so you might look at ordering in larger bulk from somewhere like eBay, or a dedicated supplier. "Mould-making latex" is usually a good search term. For extra durability of the latex in sticking to your foam, it's possible to "prime" the bare foam with some spray contact adhesive before painting your latex on (allow to get "tacky" but not completely dry to the touch like you would before gluing).
Some key points for working with latex: -
- Buy some cheap brushes, and don't expect them to last.
- Despite the above, keep the brush submerged in latex between coats, to minimise "bobbling" and formation of gross little clots of hardened latex that will get all over your weapons.
- Find a system that works so you don't have to touch the parts you're latexing. Most people either have all their weapons hung from quickly-made metal wire hooks, and hold the un-latexed grip area of a sword, for example.
- Latex mixed with acrylic paint will look clear and milky, but as the latex dries transparent the colour comes out stronger.
- Let each layer dry completely between coats. This varies markedly depending on the temperature! On a sunny day, that can be 10 minutes, but in the winter it can be hours between coats. We tended to work in batches of 50 so it wasn't lots of wasted time.
- Dried latex is super sticky and will stick to other latex with what seems like inseparable strength. If this happens (it will) don't panic, and do not pull them apart - you will ruin all your previous layers this way. Instead, either take a clean paintbrush dipped in water, and wiggle it into the seam of the join while gently pulling them apart, or you can sometimes strike the weapon with your palm in such a way it will vibrate free.
- Don't use any copper- or bronze-coloured metallic paint, since it may contain copper powder, which corrodes latex very quickly. The quest for a "true bronze" colour is a bit of a UK LARP in-joke, and most makers have their own secret recipe (some variant on silver paint + brown).
As a very broad rule of thumb, material cost (not time cost!) for a sword works out at somewhere between £15 and £20 - most one-handed UK LARP swords are sold for between £50 and £70.
If your budget is exhausted, you might have to just accept that they're not going to be perfect!
Best of luck!
(* If you do end up using this stuff, please be careful. It's very smelly, and has a long list of health warnings on the can.)
