Do these bolt straight into my factory brackets?

Yes. They mount at the factory rocker points with no drilling or modification needed. Your existing wiring harness plugs in directly.

Will I need ballasts or HID conversion equipment to run these?

Depends on what you're starting with. If your SRX is stock halogen, these accept halogen bulbs as-is. If you want to upgrade to HID or LED, that's a separate modification—these housings are compatible with aftermarket ballasts and bulbs, but you'll source those separately.

What's the return window if they don't fit?

Contact ModSupply customer service directly for your specific return window and process. Confirm fitment before installation to avoid hassle.