If your equipment is using the C-map+ cards I would have to assume that your equipment is the RL/RC series. It might be worth the price of a chart upgrade but that's about all I'd invest since they haven't made that model for several generations & don't offer a repair service on them any longer. If the radar is working, Id be happy & use the system for the radar & the charts as a backup, until it decides to quit. In the meantime, if it were me, I would be looking at a new chartplotter that you could use alongside your existing system. If the plotter was in the form of an ipad or similar, you could use it for other tasks when you weren't using it to navigate. If you decided to go with a brand name hard-mounted plotter such as garmin ,raymarine or the like, you could use that as the main tool for navigation & then expand it to 2 stations & add radar when the old system takes a powder. Either way you would have more current charts.
Enjoy that new-to-you boat!