So how does one expand their Heroscape playing on a budget?
That will be almost impossible unless you continue to get lucky on future acquisitions/discoveries. Ebay prices are unfortunately now the norm for this wonderful, but discontinued game.
Try periodic searches and advertisements via craigslist.
Auggies can sometimes have inventory of some Heroscape and has been known to ship international as cheaply as possible, but his current selection is pretty sparse at the moment. Still, it pays to check in with his site often: http://www.auggiesgamestore.com/catalog/heroscape/699
Look in at Heroscapers.com (specifically here: http://www.heroscapers.com/community/forumdisplay.php?f=110
) to see if there's anyone domestically local to you that's selling. If not, you can still sometimes get a price break from ebay pricing on some things if you are patient, but chances are fairly likely that you'll have to pay international shipping rates of some kind regardless.