Your current unit will have no problem driving the speakers, especially at lower volume levels (although you will be able to play them plenty loud as well).

I would get the speakers, enjoy them for a good while and then contemplate potential amplification upgrades.

Have fun!

When I was a younger person I could easily get my neighbors to complain about my loud music with a 35 wpc receiver and 88dB SPL @ 1 watt/1 meter loudspeakers. You should do just fine for now with a 55 wpc receiver and 91.5dB SPL @ 1 watt/1 meter loudspeakers. So, your 55 wpc will produce about 99 dB at 12 feet with those loudspeakers. That's like standing next to a gas powered lawnmower running full throttle.