I found a solution, though I will state right now that this comes about 4 years after the initial poster put this topic on the forum and I am using a different version of Virtuemart.
The price range can be implemented just using CSS. Find the ID tag for the Product Price in the cart section. This is numbered as unique for each product. With this I used the ::after CSS selecter to insert the text and style it according to the W3Schools reference:
http://www.w3schools.com/cssref/sel_after.aspexample
#productPrice7 div.PricesalesPrice::after {
content: " to $ 180.00";
}
Other products will have other numbers in the ID tags, meaning they won't be affected by this CSS styling command.
I think this is a valid hack for a one-off simple 'hack'.