Ken Penders is selling a few different pieces of original art and one script on Ebay. You can get the original art to the 5-page story “Beat The Clock” published in Sonic #11, the Princess Sally Sega Data File in Sonic #101, and/or the Julie-Su Sega Data File in Sonic #102. The bidding on the Sally piece ends on October 28 at 10:37pm Eastern Time (7:57pm Pacific), while the Julie-Su one ends at 10:57pm Eastern Time (7:57pm Pacific) on the same day. The bidding on the story ends on October 29 at 11:18pm Eastern Time (8:18pm Pacific).
Source: Ken’s Comic Book Stories and Art