ST's are by far the cheapest. On top of welding in a couple cross members to reinforce the bends on the stock you could look closely at the ST's and add a new mounting hole to the stock in the same location as the second drilled hole in the STs.
Do be warned though, you should also weld reinforcements to the tab on the control arm before beefing up the sway bar and modifying the mounting location... the whole reason Toyota switched to plastic endlinks was that they were easier and cheaper to replace when they snapped than the control arm.