Can anyone suggest a good hardware VPN proxy or router that would support 200Mbps throughput?

I recently bought a high spec router and replaces the OS for DD-WRT which worked really well except I could only get around 20Mbps from it when running a VPN on the router. I then built a VPN proxy on a Raspberry Pi running Open VPN and I could get around 25Mbps routing traffic through it. Finally I tried using an i5 laptop as a proxy and I could get it running at around 18Mbps.

Running Open VPN from a high spec gaming machine I can get over 200Mbps. A VPN is pretty processor intensive. Can anyone suggest a device that I could use as a router or proxy running a VPN that would support 200Mbps+ traffic? I could build a high spec server to do it but it would be big and costly and noisy.

Thanks in advance.