Staking plants

Between the showers I have been out trying to stake plants which are flopping about because of the rain.  The flowers get heavy with the water and bend the stems over - some are even broken.  I bought a couple of what I think of as expensive stakes to hold up a couple of things to give them a try - and yes, they work very well.  Others have the old method of tripod of canes and string - one of those broke very quickly!  It did remind me that I'd seen Monty Don make the contraptions I'd bought on Gardeners World - take a look here: home made stakes for border plants   I haven't managed to source the 6mm steel rods yet.  Anyone know any where that sells them locally?