I have seen some very high priced stuff sell on eBay and there is no reason why it is out of the question.
First of all, you are tapping into a world audience so it is much more open than just local retail. There are lots of ways to protect yourself financially, including escrow and wire transfers, since the amounts probably exceed PayPal and BidPay limits.
If you sell musical instruments now, you probably take great pictures and write good copy. It is not a great leap to high end antiques. If you sold air fresheners right now I would say you were at higher risk.
You could try one or two items that you own already and do a test. Try one with a reasonable starting price and a solid reserve and the other with a higher price and no reserve. Make sure there are lots of pictures, written details and measurements. Make your terms professional but friendly - not threatening.
Lastly, I would include in the terms the option of local pick-up, saving the buyer insurance and customs problems. Maybe they have friends or relatives near your city. This will make your high price item more attractive.
Good luck!
Lisa