Tell Me What I Need...

I`ve been all over the net and have been asking what I need to implement a passive sub (Revel Ultima) into my 2 ch setup.
What I have is very very modest by Audiogon standards but it works for me and sounds pretty ok IMHO.

I use a little Bellari VP129 phono pre that I run straight into a Parasound HCA 1500 amp (has RCA outs in back). My speakers are Revel F52`s.
The sub only has 1 set of speaker connectors (+ -)
So, I need a crossover and an amp and I want to relieve the main speakers of lower bass duty which I think is a nice idea given that they have smallish 6.5" drivers.

I`ve scribbled down a few suggestions as I`m not in any super hurry as I have a Rythmik 12 in use currently.

The factory optioned amp had 700 watts so I may need to be somewhat close or maybe not, as I only listen to music, no movies or video at all.

So what do you guys think ??