Based on this product's specifications, here are some alternatives and similar models
APC Battery Pack SUA24XLBP for SUA1000XLI — VRLA 24 V, Black, 31 kg, 170.2×439.4×215.9 mm
Summary description:
APC Battery Pack SUA24XLBP is a replacement battery module designed for the SUA1000XLI UPS. It uses Sealed Lead Acid (VRLA) technology with a nominal voltage of 24 V. The unit is finished in black, weighs 31 kg and measures 170.2 × 439.4 × 215.9 mm. Intended to restore or extend runtime for compatible APC UPS installations in server, network and telecom environments.