Good steel for back springs in slipjoints?

[J S Machine]

I have 410SS, A2, AEB-L, D2, and S7.

The 410SS and AEB-L is the most readily available, and I would like to use either one of those if possible.

 

[Calvin Robinson]

Forget the410ss, I don't know what AEB-L is, I've never used any S7 but I know that A-2 and D-2 will work, you just have to temper at the right temp.