It's a home-build aircraft...the plans will probably specify the grade of steel bar you need , it's probably a common broght cold-rolled steel but there are many different grades depending on application......if there is ant turning, therading to be done, the right selection will be more easily machined. likewise if it doed need heat-treatment.....It isn't going to be terribly high-level metallurgy, given the age of the design and the far superior material available today. If you look round, there are plenty of small engineering shops /fabricators or model engineers who have the equipment and knowledge to make and fit replacements as needed.....I'm sure the LAA can help, but fromwhat i've heard, they don't expect to spoon-feed you.....they may well know someone in your area, maybe even a local "strut" member has the time/facilities/ inclination to help you.
S N D raises a very important tip. That looks like a total no-brainer! If I owned a Turb. I'd put the spring-mod at the top of my list and given your axles are bent, I'd check the spar very carefully indeed.
Oh, and there are many spring-makers who can make to pattern or spec. anything including vehicle suspension springs,down to a tiny spring in a bracelet-catch. You may need a business directory from the local library,considering how dire "yellow Pages" are nowadays.