Oof. What version is this anyway, it doesn't show up in the footer anymore. vB3?
I just checked XenForo's pricing scheme. They don't have an integrated CMS app available, but the license is "only" $160, with built in converters for vB 3.6, 3.7, 3.8 and 4.x, with a $55 annual renewal for updates and support.
So, cheaper than Invision which is minimum (Core and Forums only) $200 upfront, and then $25 every 6 months for updates and support, but still a three-digit price tag.