Must be some glaring condition issues. Usually the 101b heads sell for a little more than 2k...if it has the class a/ab switch, it can go up a bit more.
If the deal is for the Bogner 4x12 and 101b...it should probably cost around $2800 give or take.
The only problem with that is you'd be underpowering the amp, unless you change the transformer out as well. I have one on the way that is loaded with Winged C 6550's...you should try those out...I've heard nothing but good things about these tubes in this amp, even from diehard EL34 users.
Jerry used an EL34 Shiva for almost the entire Degradation Trip recordings. That being said, if you want the best Shiva, I'd go with the 20th Ann. model. It cuts better and is more open sounding than the old Shivas. It also has more gain to get you into modern territory.
Man, you got a great deal and you can cover so much ground with that amp. I have the 20th XTC and it's insane how versatile it is. As someone else mentioned, the XTC Classic will really shine as you open it up, although the master volume is very good and sounds great at low volumes, too.
It'll be closer to a Marshall, but will still have it's own very unique footprint. It's more open than the 101b and tighter with a nicer clean. It doesn't have as much gain (hey who really needs all of it anyway), but it does have more bite which I like. Compared to the Shiva, it will be a...
For me the 20th Ann. Ecstasy is the best amp I've heard or played. It is actually easy to dial in and the switches are much more effective, whereas the 101b took some serious tweaking. It has more of a Marshall bite than other Ecstasy's and is tighter and more open sounding.
If I had to choose...