Well testing on wells with obsolete units/systems

We are seeking solutions to improve our ability to perform well tests on wells/platforms with obsolete units/systems. We are preferably looking devices that can support surveillance of subsurface and production systems.

Background:

There are obsolete/legacy and non-functioning well testing meters/systems on certain wells or normally unmanned installations (platforms) in which there are sometimes accessibility issues due to challenging weather conditions and other priorities.

Conditions are south east Asian waters, and looking at offshore platforms, focus is more on physical technologies rather than software