M_Boats: Old electronics

I have inherited a Raymarine RC435i chart plotter. I want to update the system and get a new east coast chart but I am confused by the information on how to do this for this very old system. It uses large SD cards and apparently has issues not only with more modern storage but card sizes. Does anyone have experience with working with old electronics like this and either updating or getting new charts (on really antiquated storage cards)? If so can you please point me in the right direction? Thanks Robbin M-23 Pinch Me, Marshall 22 Otter Robbin Roddewig robbin.roddewig@verizon.net