If you are looking to have a mono, non crossed over 'dual mono' system, with a single preamp driving two power amps, each powering a separate 4ohm cab (which I believe is what you want to do), I would consider trying to find a new or used Genz Benz Shuttle Max 12.2 or 12.0 (not much difference). Lightweight, LOTS of EQ, tube versus FET front end option, nice power at 4ohms per side.
This head has no 'balance' control for the two power amps, so it is only appropriate if you use two identical or very similar cabs (i.e., similar sensitivity and power handling).
Great option... super lightweight, good quality, and given Genz is being eliminated or at least absorbed into the Fender amp family, there are some great deals, with Fender support.
Of course, the Eden WT800 is a classic.