Daddario makes a 12-54: DAddarioFretted Strings » Electric Strings » XL Nickel Round Wound » EXL145 Heavy Plain 3rd 12-54
and a 12-60: DAddarioFretted Strings » Electric Strings » XL Nickel Round Wound » EXL148 Extra Heavy 12-60
For C# I use: 11-52: DAddarioFretted Strings » Electric Strings » XL Nickel Round Wound » EXL116 Medium Top / Heavy Bottom 11-52
The low string is a little loose, but not as loose as a set of 9s in standard.
GHS makes low tune sets: 11-70: Amazon.com: GHS Heavyweight Boomers Custom Lo-Tune Electric Guitar Strings Heavy: Musical Instruments
and 11-53: Amazon.com: GHS GB-LOW Boomers Low Tune Electric Guitar Strings: Musical Instruments
and a 12-60: DAddarioFretted Strings » Electric Strings » XL Nickel Round Wound » EXL148 Extra Heavy 12-60
For C# I use: 11-52: DAddarioFretted Strings » Electric Strings » XL Nickel Round Wound » EXL116 Medium Top / Heavy Bottom 11-52
The low string is a little loose, but not as loose as a set of 9s in standard.
GHS makes low tune sets: 11-70: Amazon.com: GHS Heavyweight Boomers Custom Lo-Tune Electric Guitar Strings Heavy: Musical Instruments
and 11-53: Amazon.com: GHS GB-LOW Boomers Low Tune Electric Guitar Strings: Musical Instruments