Given your parameters you might want to search for McCormack's 3-channel amp(HT3?). It might be a little more than you're looking to spend, but given its smooth performance it may match up very well with your RBHs. If you like it you always have the option later of having Steve McCormack perform one of his famous Revision upgrades, which will make it into a killer of an amp. Best of luck and congrats on the new speakers.
Tim
Tim