It turns out that the website I was intending on ordering supplements from (smartpakequine.com) only ships to the US! So that's a no go.
As for what type of supplements, I'll likely be getting one for gastric health (as she's a bit prone to ulcers) and then one for her joints.
I'm also wondering what's the best alternative to grain for a horse prone to ulcers who also needs to pick up a bit of weight, I've heard rice bran and beet pulp are good but I'm wondering where to find those. Another thing is ration balancers. Are there any certain brands to be looking for?
I'm basically thinking that we'll sort out amounts with the vet, and get his opinions on whatever diet ideas I can come up with. She'd be out in the pasture 24/7 with about seven other mares (although three go in at night) so it'll be nice for her to have the access to grass at all times.. but I'm definitely going to be feeding supplements and a ration balancer as well as something to get some more weight on.
I've done a bit of research on the different types of sugars, up to things like oils as well.
So, another question is, would vegetable oil (also read that it'd be considered a soybean oil) be a good choice to help put weight on as well plus make the supplements and ration balancer a bit more appetizing maybe?