Welcome aboard NorEyeWest. I can suggest a few options for your needs.
You can buy the Garmin BWCA chip that plugs into the back or a download. I have 4 Garmin chips of various areas and they all are awesome. They run about $75-99 each. I don't have the BWCA chip but I do have the USGS 24000 topo chip that is just about the same information.
You can buy the PaddleNav chip and download $79.00 or Download only for $55.00. I have seen the screenshots of these and I really like them. Good color contrast and there is also lake depths.
You can join the GPS forum at the bottom of the page here and search for the thread that talks about a free chip, pay it forward I think. You might be able to sweet talk one of the members here to burn you one. Click on this link at the bottom of the page.
You could also do a search on the GPS forum for the free information you can download into your GPS that covers what you want. Many here would be glad to help you out with the free downloadable information.
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