Yes there is!
You can always find up to date module here: https://github.com/blesta/module-proxmox
If you have issues with it, feel free to mention me on blesta discord where I'm often active
If something doesn't work properly in current 3.0 version, please open issue on github Also any ideas, improvements, bug fixes are nice to see.
https://github.com/blesta/module-proxmox