If you want matching algorithms, your Aqua Lung choices are the watch sized i200c for $389, intermediate size i300c for $329 or puck size i100 for $229.Hi @edwants2dive
Your Aqua Lung computer runs PZ+ deco algorithm. It is a proprietary algorithm based on Buhlmann. Only another computer running PZ+ would have identical NDLs. PZ+ is moderate, or middle of the road, in the conservative to liberal spectrum. It runs somewhere near a Buhlmann GF high of 85.
There is one other nice option. You can still find the watch sized Oceanic Geo 2.0 for about $280. It has the same corporate parent as Aqua Lung and you can set it to use the same PZ+ algorithm. The only thing it lacks compared to the i200c is the ability to download logs via Bluetooth, which you presumably don't care about for a pure backup computer.