don't expect to find much 60's stuff listed at "usual retailers" on the net, but if you go to a good auto store, NAPA or such, they'll have most parts listed for ya
but no point in spending money that won't fix the problem! your problem isn't due to the drag link, which only fits on the shaft in one exact splined position, they're all "non adjustable" - see the 'steering box - non-truck related' post in the greasy spoon
tie rod is a different thing tho, for adjusting the toe in/out, don't try to fiddle your steering wheel that way
Bill