Justin, since your budget is $1500, you should consider the Decware Zen Triode Dual Mono Integrated amplifier (simply known as Zen Integrated):
http://www.decware.com/integrated/zint.htm
It is VERY flexible (has a couple of biasing options, plus you can always roll the tubes; 4 inputs; several output configurations), powerful enough for your RF-5's (which are 99db, more than enough for 7 watts per channel that this dual-mono integrated provides), and has great testimonials from multiple people.
Unfortunately, I did not hear it myself - I am now getting Zen Select instead (my budget is not as big as yours :-), but there is one very comprehensive review of this amp:
http://www.tnt-audio.com/ampli/decwarese34i_e.html
plus there might be several reviews on audioreview.com (look here for all reviews of Decware Zen amps series: http://www.audioreview.com/Amplifiers/Decware+Zen/PRD_115750_1583crx.aspx).
If you explore decware's web site, you'll find a lot of other interesting stuff, such as papers on audio, history of zen amps, and very helpful forums.
Good luck finding your perfect combination!
Maxim.