Get in touch with Anne at Sea Breeze Books for electronic and paper charts. link
She's an experienced mariner and she owns that bookstore. She routinely outfits everyone from cruise ships and mega yachts down to day sailors with exactly the current charts and book resources that they need. I'm always amazed at the research she does to support her customers cruising the world's oceans. I often stop in her store for a chart or book and always ask what "package" she's putting together for a cruiser or mega yacht. Fun to learn about the travels of others.
Tell her your budget woes--she is used to cruisers and knows we're a frugal bunch--and ask her to get you what you need at a minimum NOW and for advice regarding the rest. You do have 8 weeks and you might find another cruiser with charts that you can purchase. Further, you might be able to swap charts with cruisers to get the detail you need of particular areas. I would NOT rely on electronic charts alone. I hope that you have all your paper charts in order???? This, IMHO, is far more important to you. You can't count on electronic charts and a GPS to keep you out of harms way--you'll need your paper charts too.