I sent in my aquameter off my '76 hunter 30 because it had a cloudy lens as well to Viking optics in MA, they were quite helpful. They quoted me about $180 for a new dome, fluid etc. I asked their rec. on doing the repairs vs buying a new binnacle mount Ritchie DNP-200 which they sell at rock bottom prices compared to other sellers, they recommended the new one which I got for less than $300.