I have used this type of reverb in one of my builds. I got a 4F... reverb tank for free and was looking for a way to drive it with a tube.
These tanks have an input impedance of around 1500 ohms and are usually used with solid state drivers.
The driver circuit is basically just a 'normal' grounded cathode stage but with a beefy tube and a pretty high idle current (and therefore low output impedance) which is needed to drive the tank. The tank is coupled via a coupling cap to prevent DC current from flowing through the driver coil. The main advantage is the absence of a reverb transformer. The disadvantages are higher power consumption, more heat and the need for a bigger tube.
Initially I copied the Traynor circuit but made some changes that improved its performance. Traynor uses a power pentode in triode mode and a high power resistor in the driver stage. This worked for me to some extent but didn't give enough reverb depth. Using the pentode as a pentode improved this somewhat but the most significant improvement was the use of an inductor instead of the power resistor. I used the primary winding of a small power transformer which is cheap and readily available.
I used a PCL86/14GW8 (6GW8 is the 6V heater variant) which is a power pentode and a signal triode similar to a 12AX7 in one bottle. An ECL82/6BM8 will also work but needs a higher input signal level. With these two-in-one tubes you can build a 1-tube reverb without transformer that can be added to any amp just as tubenit's circuit.
I have attached a schematic of my reverb module. A coupling cap may be needed at the input, depending on your circuit.
Sorry, I only have it in JSchem format. You can download JSchem from http://dhost.info/jschem
if you don't have it already.