Amp to Match a Van Alstine PAT 5

I have the pleasure of owning a Van Alstine modified Dynaco PAT 5 preamp and am looking for some input concerning upgrading my current Parasound HCA 800II. My question is will a Dynaco/Van Alstine amp work best or is there another combination that really shines. Associated equipment is a Sonagraphe SGA-3 turntable with Grace 707 arm and Benz Micro cartridge, NAD 5425 CD, Spendor SP 2/3 speakers and my primary playback medium is vinyl.
I would appreciate any input on a potential upgrade.