help me choose a tube preamp mcintosh/b&w

hello guys, i've been enjoying my decco as a DAC/pre feeding into my mcintosh 7100, but i'm thinking about getting separates now

for the dac, it'll either be a DACmagic or PS audio DLIII

however, i have no idea what's out there for preamps... i would like to go w/ a tube preamp since the 7100 is SS

i'm also on a budget and need to keep it around 500 give or take

thanks for any suggestions