Homebrew charts on Raymarine plotters?

[Jammer]

I've been experimenting with OpenCPN and have started converting and calibrating these maps of some shallow rivers near me:

Minnesota River State Water Trail: Ortonville to Granite Falls: Minnesota DNR

As far as I know there's no coverage for them in any electronic charting source.

For the last couple of years, I've been using the Navionics plotter app on my Android phone while on canoe trips. Sounds like overkill, and maybe it is, but it's a substantial help when on a river you've never seen before and where the landmarks identifying a takeout location are difficult to pick out by eye.

I may end up in a similar situation (albeit in deeper water) with the sailboat. I am presently planning on getting Raymarine electronics. Anyone know if there is a way to convert scans or PDF files for use on their chartplotters, as there is with OpenCPN?

[ ETA: I did check the Raymarine documentation and it was not helpful ]