The supply of He-Ne laser tubes suitable for use in green (543 nm) Zeeman stabilised lasers is now an issue as the main manufacturer has ceased production. These lasers are in use at many EURAMET NMIs, typically within the Gauge Block interferometers manufactured by Hexagon Metrology UK. In order to continue the manufacture of these lasers and to support future upgrades, replacements, repairs, a consortium of NMIs will collaborate and exchange information on several aspects of stabilised lasers for interferometer use. Tasks will include: exchange of information about laser components and their supplies; consorted campaign to persuade a laser manufacturer to manufacture tubes to a common design specification; work on novel stabilised laser designs (e.g. laser diodes).