brainbug007, just do the math. 22 bushe tubes 35 mm each. That's 770 mm. So, 1 m should be enough and you should have some room for error.
3 mm strip? Frankly, I'm not sure how much of it you need. There are many parts out of 25x3, 30x3, 40x3 strip. There is no 3 mm strip available here, so I just got a 1000x1200 mm sheet and still have about half of it left.
As for the wishbone tubes, it's also easy to do the sums: 3.92 m of 25 and 2 m of 20. Also, it's wise to have some extra in case you don't get it right the first time.
Hacksaw? That's indeed hard. You need an angle grinder!
I got all the 10 and 5 mm plates laser cut, and some precise 3 mm plates: all of the rear upright parts, steering support. I also got all the suspension brackets laser cut and bent in an engineering shop. The rest of the plates are pretty easy to fabricate with an angle grinder. I'd say the hardest part is the larger holes: in the pedal box for the master cylinder, the bolt access holes in the rear damper mounts. Without the right instruments they are really tedious. Lots of drilling, filing, grinding and cursing.
Later I ended up buying another offcut of the 5 mm plate for the engine mounts.