I have an account with Heritage Auctions but, so far, haven’t acquired anything through them. Much, if not most, of the high-end original art for comic books, comic strips, and cartoons is handled by Heritage. The high-resolution scans provided by HA are valuable resources in studying the work of many noted artists.
There are only a few days remaining to bid on page #9 from Amazing Spider-Man #7. Right now it’s going for $54,000, including the “buyer’s premium.” This early example of Steve Ditko’s work on the series clearly shows where he inked with a pen, and where he instead used a brush.