Adding center channel to HiFi setup

Greetings,
New member here. Like many others, I have been slowly transitioning from a surround sound system to a HiFi system that includes vinyl as a primary listening source.

However, my wife and I still enjoy movies and TV, and for that reason I have kept a center channel.

Current setup:
L/R Polk Audio RTI A7s
C Polk Audio CSI A6
Marantz NR1403 Slimline 5.1
AudioTechnia LP120
Schiit Audio Mani Preamp

The glaring weak point in my system is the painfully underpowered Marantz, which can only put out about 50w per channel. The Polks are thirsty, so the next move is a proper amp.

The problem is that most of the research that I have done on proper HiFi amps yields 2 channel results.

The only solution that I can think of is retaining a receiver with preamp outputs for the L/R to output to the amp, and leaving the receiver to drive just the center. It just seems wasteful to incorporate a receiver into this system to effectively drive only one channel.

Thoughts/suggestions? If there is another thread that has already explored this issues, please post it in response. Thanks in advance.

 

Bump?

 

Maybe go for a surround receiver w more power? There are plenty of 3 channel amps though. One channel amps also.