I posted a similar question about upgrading an old rechargeable stinger.
TerraLux was the only answer given. That might be the only option outside of sending it to someone on here to custom build/modify.
You talking about the TLE-ST Dano?
A good way for an very good update is the Streamlight Stinger C4 upgrade kit, Part Number: 75712, there is all you need for replace.
I tested it for myself. Great Beam, good spot, i was surprised from it.
That's a whole light. The Terralux is just a bezel and LED module.
That is not a whole light, it is Original Streamlight Upgrade Kit !