I will try and ask the place i bought the metal from.I don't know who operates where you are, but is there a linde or air-liquide place anywhere near? Looks like it still won't be 'cheap' mind.
Or, any bodywork or fabrication places near you? Can you find out who they use?
Solid wire is much less variable than fluxcore. There is still variability of course, but I've found if you steer well clear of the sub 1kg rolls and head for 5kg or 15kg the quality is more consistently good.
I doubt they will price match but its worth a try. I suspect they charged me more as i'm a foreigner.The quicker you do it the higher the chance imo.
You might get charged a month's rent though - maybe an 'admin' fee too.
If you tell them the reason you want to cancel, they may even price match?