Any a-arms should be fine, they won't affect what knuckles or driveshafts you can use. Probably could use the stock knuckles, I think I did see someone try that route by reaming the bearing recesses to fit shims now that you mention it...
I think I'll probably just go with the traxxas CVD's as all I need is in there and I don't have to try and figure it out, once I get up and running and if I find issues then I may try to convert to the Losi ones...
Whats your opinion(s) on the Flm arms?