Do you need the whole endlink, steel and all? or just the bushings? The bushings should be easy to find, mine looked pretty universal. If you need the whole thing and cant find some proper stuff you might be fabricating something, which shouldn't be too hard. I got lucky with mine.

This might not help you, but when i bought my 72 Roadrunner it came with the (original) bar in the trunk and a bag ov ancient Mopar performance (Direct Connection? stock replacement anyways) endlinks with it. But there was no way to attach them. The endlink itself just kinda came to a stub where it attaches to the bar and we had to weld it to the bushing bracket. I was pretty concerned about doing that, but there was no other way (the guy i had do it is a suspension expert and knows his Mopars). We welded the endlinks to the bar, then welded some brackets onto the frame because there were none there and we couldn't find anything from a donor car anywhere at the time.

Anyways, despite my concerns about welding the bracket with the rubber bushing still inside and maybe even the whole idea ov the set-up its held solid and worked really well for years. I drive my car hard too (and have broken a rear sway bar in my 96GT) so i'm positive it would have broken by now if there was a problem.