I'd like to import my existing WP site which has upwards

I’d like to import my existing WP site which has upwards of 65,000 posts (products) into MarketPress and I have several questions about the best way to proceed.

1. The existing site (www.rsci.com) I built several (6-7) years ago as a product catalog, where I used Posts as the child products and Categories as parent products. – QUESTION: Can I convert the existing Posts (products) and their parent Categories into MarketPress products and categories?

2. I have a CSV file with the entire product line though the headers have different values than the MarketPress example datasheet. – QUESTION: Is there a mapping plugin/tool that might allow me to manually map corresponding headers OR is my only option is changing the existing CSV headers to the example file?

Thanks!