I'm glad you didn't lose your virginity but I'm going to vote for '
SOL '.
Even if you bought it yesterday, the breakage point has a high
probability of being caused by user error. Torque that seatpost down
nice and tight? ;-)
Try asking the folks at RS (I'd leave out the Ebay part). I've had mixed
results with similar complaints, some vendors (Blackburn, Terry) have
been really good, not requiring receipts, just sending in the broken
parts. It doesn't hurt to ask, it may even help them improve their product.