Does it really need to be analog? The BossEQ is probably your best bet for price/size/features. A stereo analog EQ is usually double the size of its single channel equivalent.
Analog pedal EQs can be a bit noisy and not really intended for line level, and I don’t think there’s a stereo one out there. But in terms of doubling pedals, you have some parametric options that take up less space than the Empress. There’s the Revival Electric Metric, the WMD Utility Parametric EQ, or the Wampler Equator.
In terms of desktop-sized outboard, the Golden Age Project EQ73 is probably your best bet for size/price/quality. Single-channel though, but you could get two and stack them (one is only a bit pricier than a pedal, around $300USD new).
In terms of 500 series, the dbx 530 I think is the cheapest single-channel EQ. Two of those in a Lindell 503 or Radial Cube chassis would be pretty portable, cost less than $800 depending on the chassis.