Integrated Tube Amps with Subwoofer out?

You can use this for $40- Russound ADP−1.2 Speaker Level. I used this to run dual subs out of Leben amp.

Itis not necessary to have a preamp out for a Subwoofer,crutchfield sells a adapter 
you just put a awg 16/wire in the + - for each side of adapter ,and either a 
banana or spade into speaker terminal it is actual more accurate 
and crutchfield , or call SVS subwoofers they can tell you exactly what it is called for under $30 I used one with my Krell integrated worked great. 

Primaluna integrated amps have one. All tube. 
Decware has a line out intended for subs as an option. They add tube rectification which is awesome too. 

Use any integrated you want. Simple elegant solution. Give Jensen a call and they will set you up with any type connection that fits your situation. Under $200 I believe, very friendly service. 
https://www.cs1.net/products/jensen_transformers/SC-2NR.htm

Primaluna has sub out