It's a sketchy situation in some ways. And no, you can't bid on it if you're the seller. If you do it using a second identity, it might even be criminal, but will certainly get you banned from the 'Bay.
Here's what I would do if I were you.
1) Investigate sold listings, KEH and other resellers' offers, and even B&M stores if you have any around.
2) Determine what you are personally willing to pay for it, and set that as the seller's reserve price.
3) Put it up for auction, with a reasonable timeframe, no "Buy it now" price, and see what develops.
4) If it goes for more than the reserve, then you've maximized your friend's return, certainly more than a wholesale offer, even with the eBay fees.
5) It it doesn't reach the reserve price, you should withdraw the item and buy it directly from your friend at the reserve price.
This depends on you being entirely ethical in all respects, but it's a way to give you a chance to buy it at a fair price. You should probably explain the plan to your friend up front and explain how you determined what you were willing to buy it for.
Andy