Yes, the tune of the Super Deluxe GENIE shock can be changed using part number 11.4118.096.025 (REAR SHOCK TUNE ASSEMBLY (INCLUDES SHIMS FOR COMPRESSION AND REBOUND TUNE CONFIGURATIONS) - SUPER DELUXE AIR GENERATION-D (2027+)). Shim stack information can be found in the Rear Shock Piston Tuning Guide.
RockShox service kits and spare parts are best obtained through your local shop or dealer. See our dealer locator, below, to find a dealer near you. If no one is currently listed near you, then please search for local shops via your preferred web browser.
https://www.sram.com/en/dealer-locator
Manuals and additional information about RockShox and SRAM components can be found at our service site, linked below.
https://www.sram.com/en/service
Further questions?
Reach out to Rider Support by Asking A Question at the link below.
https://www.sram.com/en/rockshox/campaigns/rockshox-rider-support