I'm also curious as to what a "loose" control arm means. Did the ball joint pop out? Or is the inner bushing completely shot? Because other than that, I can't think of any way for it to be "loose".
If one UCA has failed, there's no reason to think the others are not far behind, and kits that include the UCA's and outer TRE's are not expensive. But before you disassemble your suspension, go ahead and start soaking the UCA pinch polt in penetrating oil (i.e. NOT WD-40; use P'Blaster, Liquid Wrench, or a 50/50 mix of ATF and acetone-based nail polish remover) once or twice a day while you wait for parts. Soak it at the bolt end, nut end, and at each UCA slot.