You can get an OEM Honda Keyfob for $40-$50 on eBay, there are also websites that specialize in selling key fobs for all brands, they charge about $70.
I've not done much research but you most likely can program a new remote yourself, locksmiths do it all the time. The dealer will charge a small fortune though. Why? Because they can and people who don't know better pay the high cost.