Thomastik makes a fifth-tuning Spirocore set. (called the Red Mitchell set)
It's 100% metal so no problem with a mag pickup!
Pirastro Obligatos are now available in a fifth-tuning set, but I'm not sure they work well with a mag pickup, since the core is synthetic.
However, you can also that kind of setup:
1st string: a solo-tuning G (A)
2nd string: a regular D
3rd string: a solo-tuning E (F#) tuned up to G
4th string: a low C or even a low B tuned up to C
With this setup you get a much wider choice.
Hope this helps!
It's 100% metal so no problem with a mag pickup!
Pirastro Obligatos are now available in a fifth-tuning set, but I'm not sure they work well with a mag pickup, since the core is synthetic.
However, you can also that kind of setup:
1st string: a solo-tuning G (A)
2nd string: a regular D
3rd string: a solo-tuning E (F#) tuned up to G
4th string: a low C or even a low B tuned up to C
With this setup you get a much wider choice.
Hope this helps!

