brake levers without springs in them still work .. because the brakes have return springs..

[Business] its in no ones economic interest to ship globally and inventory just a spring.

I've had to try to reposition the lever spring on a number of levers. Some like many Shimano are easily scavenged from other levers, Campy's Ergos use the shift blade's hub spring for the brake lever. Many levers don't have such broad use/availability or easy access/replacing of the spring. So if you strike out and if you can use that lever on the front brake. The shorter cable run will result is less casing friction losses. Additionally some calipers have an adjustable spring and if so then increase that best you can. Andy

You can get later model springs for Shimano and Campy models but for older levers it will be difficult and probably pure chance searching through a box of levers at a community bicycle co-op.

then replace it / them as a pair...loose and jiggly can be as results of a crash history bike falling over, etc.

That doesn't sound right. If the caliper is retracting normally, it should be pulling the lever taut. Maybe you have too much slack in the cable? Perhaps the hoods are interfering in some way?