UPS for phones at desktop

[Drew Gibson]

I have to power groups of 5 Aastra 480i phones plus a small PoE switch 
(Netgear FS116P)  for 2-3 hours. There has to be 1 UPS per group due to 
the office layout.

Has anyone found a low VA/ long battery life UPS at a reasonable price?
What are others using?

regards,

Drew