Up for your review is a Cyber Power PR1500LCD. Tried to recharge the two internal 12V 18 amp batteries for a day and unit says to replace. If I get replacement batteries the price goes up. You might have batteries already from a failed unit and this would work to swap out.
PLEASE NOTE: RMCARD205 optional card is installed for remote access. Alone prices are 129.00 on eBay used. Shown installed in back of unit in photo # 2
Capacity: 1500 VA / 1500 W
Topology: Line Interactive
Waveform: Sine Wave
Output: 120 VAC ± 5%
Plug type & cord: NEMA 5-15P, 6 ft. cord
Outlet types: 8 × NEMA 5-15R
Communication: USB, Serial, SNMP, Relay, EPO
Management software: PowerPanel® Business Edition
Remote management: Yes, with optional RMCARD205 (INSTALLED)
For Manufacture product specs
https://www.cyberpowersystems.com/product/ups/smart-app-sinewave/pr1500lcd/