Hey Eric )
Can you think of support of the SCCP protocol? I would then buy a lot of Cisco 794X on the market for $ 5 apiece ))
Hi John,
Cisco 794x should have sip firmware, you can fresh the firmware if you just need the normal calling features.
https://software.cisco.com/download/home/281346593/type/282074288/release/9.4(2)SR1