I pay £31 for the same and know I am lucky to have a supplier who does cash sales, nothing is any bother and will deliver anything for a tenner within 24 hours.
I have an assortment of odds and ends of box/flat/angle etc. lying around from jobs at work... I'm not a fabricator by trade so my materials estimating errs on the side of caution and I always end up ordering more than I need...
the place i get bits from is always worth a trip on a saturday morning when the bosses are out and the lads are doing overtime or there own projects, i nip in barter for what i want and pay cash, always nice to get one over on there boss the tight fisted... or is that me!?!?! lol
Paid £215 for 3 x 2.4 mtr of 125mm 'U' channel (about 6 mm thick), plus 2 x 2mtr lengths of 50mm angle (3mm thick).
Had eight 18 mm holes drilled as well.
If you buy material cut to length from metal supermarket type places, you are generally paying at least 2-3 times what a proper steel stockholder would charge. But its convenient and it seems most people dont mind paying over the odds.