The Rascher is
$105. That is a bit pricey, I'll grant. (All proceeds got to music education, so that could be a plus, too.)
I think I've held a Buescher soprano. Once. That was about it. I have used the Rascher on a gold-plated True-Tone bari and felt that the bari was probably the second best sounding horn I've ever played.
The alto True-Tones (don't know about tenors) had a variety of different necks, depending on how old the horn is. That really shouldn't apply to higher or lower horns, but it obviously can color people's comments.
So, I think you've got a few alternatives:
* Ask someone that owns one of these what his favorite mouthpiece is and see if it works for you
* Get an Otto-Link
* Get a Rascher
* Find a mouthpiece on eBay
Anyhow, you might be interested in another mouthpiece that's around the same age as your horn. For instance, the Goldbeck metal mouthpieces are relatively common on eBay and they were approximately contemporary. Hey, even Conn Eagle mouthpieces from around that time looked pretty simular to the original Buescher mouthpiece.
Good luck. We're all counting on you.