The lowest I would ever recommend for a tube amplifier would be Yaqin as mentioned above. Any less and you are seriously gambling your money. I'd also stay away from older Jolida units as they have issues with the PCB boards - I've been down that road with a SJ302a and it wasn't fun or cheap. Shuguang also had some decent amps but I'm not sure you'd find any at a 'budget' price.
If you wanted to get a feel for what tubes were and not worry about the hassle, I'd recommend checking out the Dayens Ampino solid state integrated. Its got that tube sound to it and would be a safe bet to see if you want to jump down that rabbit hole. When I got this in, my Shuguang 845 monoblocks set to the side for several months while I enjoyed the Ampino.
If you wanted to get a feel for what tubes were and not worry about the hassle, I'd recommend checking out the Dayens Ampino solid state integrated. Its got that tube sound to it and would be a safe bet to see if you want to jump down that rabbit hole. When I got this in, my Shuguang 845 monoblocks set to the side for several months while I enjoyed the Ampino.