Distributor springs

I have a Mopar distributor that uses Mallory's YT advance. The Mallory spring kit comes with springs ranging from pink **edit to change from lb. to oz. Pounds is wrong** (6oz.) to orange (13oz.) Mallory's timing curves show that two orange springs (the heaviest) will max out at 2500rpm with a 20º limit in the distributor.

The weights are my numbers, measured via scale with the springs at 3/4".

I want to raise that rpm, getting 18º at 32-3400rpm.

Other brands of springs should work, but it would be helpful to know what the options are.

Does anyone know the pull/tension of other brands of springs? MSD maybe? I can double a spring, but I'd rather not. I can reduce the weight value, but I'd rather not fuss with that either. I am looking for the simplest approach, and a 'correct' (for my intended use) spring is exactly that. Springs in the upper teen range would be great...if I can get them.

For $20-some, I can order an MSD kit and see what's in it. If someone can tell me, I won't have to waste the coin.

Thanks.